diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepository.java
index 07b7f175c9..dbea8b4b3b 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepository.java
@@ -32,7 +32,7 @@ public class InMemoryAuditEventRepository implements AuditEventRepository {
 
 	private int capacity = 100;
 
-	private Map<String, List<AuditEvent>> events = new HashMap<String, List<AuditEvent>>();
+	private final Map<String, List<AuditEvent>> events = new HashMap<String, List<AuditEvent>>();
 
 	/**
 	 * @param capacity the capacity to set
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/listener/AuditApplicationEvent.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/listener/AuditApplicationEvent.java
index b02a5c4eed..b78fd24966 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/listener/AuditApplicationEvent.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/listener/AuditApplicationEvent.java
@@ -30,7 +30,7 @@ import org.springframework.util.Assert;
  */
 public class AuditApplicationEvent extends ApplicationEvent {
 
-	private AuditEvent auditEvent;
+	private final AuditEvent auditEvent;
 
 	/**
 	 * Create a new {@link AuditApplicationEvent} that wraps a newly created
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/AuditAutoConfiguration.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/AuditAutoConfiguration.java
index 6a87e9bf36..4bc82fac4f 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/AuditAutoConfiguration.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/AuditAutoConfiguration.java
@@ -38,7 +38,7 @@ import org.springframework.context.annotation.Configuration;
 public class AuditAutoConfiguration {
 
 	@Autowired(required = false)
-	private AuditEventRepository auditEventRepository = new InMemoryAuditEventRepository();
+	private final AuditEventRepository auditEventRepository = new InMemoryAuditEventRepository();
 
 	@Bean
 	public AuditListener auditListener() throws Exception {
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/CrshAutoConfiguration.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/CrshAutoConfiguration.java
index 76cf60a7e0..8e1f4035de 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/CrshAutoConfiguration.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/CrshAutoConfiguration.java
@@ -340,9 +340,9 @@ public class CrshAutoConfiguration {
 	private static class BeanFactoryFilteringPluginDiscovery extends
 			ServiceLoaderDiscovery {
 
-		private ListableBeanFactory beanFactory;
+		private final ListableBeanFactory beanFactory;
 
-		private String[] disabledPlugins;
+		private final String[] disabledPlugins;
 
 		public BeanFactoryFilteringPluginDiscovery(ClassLoader classLoader,
 				ListableBeanFactory beanFactory, String[] disabledPlugins)
@@ -409,7 +409,7 @@ public class CrshAutoConfiguration {
 	 */
 	private static class SimpleFileSystemDriver extends AbstractFSDriver<ResourceHandle> {
 
-		private ResourceHandle root;
+		private final ResourceHandle root;
 
 		public SimpleFileSystemDriver(ResourceHandle handle) {
 			this.root = handle;
@@ -463,7 +463,7 @@ public class CrshAutoConfiguration {
 	 */
 	private abstract static class ResourceHandle {
 
-		private String name;
+		private final String name;
 
 		public ResourceHandle(String name) {
 			this.name = name;
@@ -480,7 +480,7 @@ public class CrshAutoConfiguration {
 	 */
 	private static class DirectoryHandle extends ResourceHandle {
 
-		private ResourcePatternResolver resourceLoader;
+		private final ResourcePatternResolver resourceLoader;
 
 		public DirectoryHandle(String name, ResourcePatternResolver resourceLoader) {
 			super(name);
@@ -505,7 +505,7 @@ public class CrshAutoConfiguration {
 	 */
 	private static class FileHandle extends ResourceHandle {
 
-		private Resource resource;
+		private final Resource resource;
 
 		public FileHandle(String name, Resource resource) {
 			super(name);
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfiguration.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfiguration.java
index 95f95acf0f..a9c924a0f0 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfiguration.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfiguration.java
@@ -78,13 +78,13 @@ public class EndpointAutoConfiguration {
 	private InfoPropertiesConfiguration properties;
 
 	@Autowired(required = false)
-	private MetricReader metricRepository = new InMemoryMetricRepository();
+	private final MetricReader metricRepository = new InMemoryMetricRepository();
 
 	@Autowired(required = false)
 	private PublicMetrics metrics;
 
 	@Autowired(required = false)
-	private TraceRepository traceRepository = new InMemoryTraceRepository();
+	private final TraceRepository traceRepository = new InMemoryTraceRepository();
 
 	@Bean
 	@ConditionalOnMissingBean
@@ -170,7 +170,7 @@ public class EndpointAutoConfiguration {
 	protected static class InfoPropertiesConfiguration {
 
 		@Autowired
-		private ConfigurableEnvironment environment = new StandardEnvironment();
+		private final ConfigurableEnvironment environment = new StandardEnvironment();
 		@Value("${spring.git.properties:classpath:git.properties}")
 		private Resource gitProperties;
 
@@ -198,7 +198,7 @@ public class EndpointAutoConfiguration {
 
 	public static class GitInfo {
 		private String branch;
-		private Commit commit = new Commit();
+		private final Commit commit = new Commit();
 
 		public String getBranch() {
 			return this.branch;
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/ErrorMvcAutoConfiguration.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/ErrorMvcAutoConfiguration.java
index 2b6b0c8712..f4de7e4c82 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/ErrorMvcAutoConfiguration.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/ErrorMvcAutoConfiguration.java
@@ -89,7 +89,7 @@ public class ErrorMvcAutoConfiguration implements EmbeddedServletContainerCustom
 	@Conditional(ErrorTemplateMissingCondition.class)
 	protected static class WhitelabelErrorViewConfiguration {
 
-		private SpelView defaultErrorView = new SpelView(
+		private final SpelView defaultErrorView = new SpelView(
 				"<html><body><h1>Whitelabel Error Page</h1>"
 						+ "<p>This application has no explicit mapping for /error, so you are seeing this as a fallback.</p>"
 						+ "<div id='created'>${timestamp}</div>"
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfiguration.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfiguration.java
index d6ca68499e..5c78d6d7ee 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfiguration.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfiguration.java
@@ -123,7 +123,7 @@ public class MetricRepositoryAutoConfiguration {
 
 		@Autowired(required = false)
 		@Qualifier("metricsExecutor")
-		private Executor executor = Executors.newSingleThreadExecutor();
+		private final Executor executor = Executors.newSingleThreadExecutor();
 
 		@Bean
 		@ConditionalOnMissingBean(name = "metricsChannel")
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/BeansEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/BeansEndpoint.java
index 83fed278c8..3d5542d032 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/BeansEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/BeansEndpoint.java
@@ -39,9 +39,9 @@ import org.springframework.core.env.Environment;
 public class BeansEndpoint extends AbstractEndpoint<List<Object>> implements
 		ApplicationContextAware {
 
-	private LiveBeansView liveBeansView = new LiveBeansView();
+	private final LiveBeansView liveBeansView = new LiveBeansView();
 
-	private JsonParser parser = JsonParserFactory.getJsonParser();
+	private final JsonParser parser = JsonParserFactory.getJsonParser();
 
 	public BeansEndpoint() {
 		super("beans");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/HealthEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/HealthEndpoint.java
index 6821bb2414..1b19355ab6 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/HealthEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/HealthEndpoint.java
@@ -28,7 +28,7 @@ import org.springframework.util.Assert;
 @ConfigurationProperties(name = "endpoints.health", ignoreUnknownFields = false)
 public class HealthEndpoint<T> extends AbstractEndpoint<T> {
 
-	private HealthIndicator<? extends T> indicator;
+	private final HealthIndicator<? extends T> indicator;
 
 	/**
 	 * Create a new {@link HealthIndicator} instance.
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/InfoEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/InfoEndpoint.java
index a9ce11b6c6..5a87eaa749 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/InfoEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/InfoEndpoint.java
@@ -31,7 +31,7 @@ import org.springframework.util.Assert;
 @ConfigurationProperties(name = "endpoints.info", ignoreUnknownFields = false)
 public class InfoEndpoint extends AbstractEndpoint<Map<String, Object>> {
 
-	private Map<String, ? extends Object> info;
+	private final Map<String, ? extends Object> info;
 
 	/**
 	 * Create a new {@link InfoEndpoint} instance.
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/MetricsEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/MetricsEndpoint.java
index 286f4e61ba..478eb1d131 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/MetricsEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/MetricsEndpoint.java
@@ -31,7 +31,7 @@ import org.springframework.util.Assert;
 @ConfigurationProperties(name = "endpoints.metrics", ignoreUnknownFields = false)
 public class MetricsEndpoint extends AbstractEndpoint<Map<String, Object>> {
 
-	private PublicMetrics metrics;
+	private final PublicMetrics metrics;
 
 	/**
 	 * Create a new {@link MetricsEndpoint} instance.
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/TraceEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/TraceEndpoint.java
index cf69bb6b56..2227f81c98 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/TraceEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/TraceEndpoint.java
@@ -31,7 +31,7 @@ import org.springframework.util.Assert;
 @ConfigurationProperties(name = "endpoints.trace", ignoreUnknownFields = false)
 public class TraceEndpoint extends AbstractEndpoint<List<Trace>> {
 
-	private TraceRepository repository;
+	private final TraceRepository repository;
 
 	/**
 	 * Create a new {@link TraceEndpoint} instance.
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/VanillaPublicMetrics.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/VanillaPublicMetrics.java
index 37c4e1daa8..de647636c0 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/VanillaPublicMetrics.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/VanillaPublicMetrics.java
@@ -31,7 +31,7 @@ import org.springframework.util.Assert;
  */
 public class VanillaPublicMetrics implements PublicMetrics {
 
-	private MetricReader reader;
+	private final MetricReader reader;
 
 	public VanillaPublicMetrics(MetricReader reader) {
 		Assert.notNull(reader, "MetricReader must not be null");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBean.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBean.java
index 086b5a883c..a61bb35e18 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBean.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBean.java
@@ -35,9 +35,9 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 @ManagedResource
 public class EndpointMBean {
 
-	private Endpoint<?> endpoint;
+	private final Endpoint<?> endpoint;
 
-	private ObjectMapper mapper = new ObjectMapper();
+	private final ObjectMapper mapper = new ObjectMapper();
 
 	public EndpointMBean(String beanName, Endpoint<?> endpoint) {
 		Assert.notNull(beanName, "BeanName must not be null");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBeanExporter.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBeanExporter.java
index b197a8e7a0..172413b5b0 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBeanExporter.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/EndpointMBeanExporter.java
@@ -66,7 +66,7 @@ public class EndpointMBeanExporter extends MBeanExporter implements SmartLifecyc
 	private final MetadataNamingStrategy defaultNamingStrategy = new MetadataNamingStrategy(
 			this.attributeSource);
 
-	private Set<Endpoint<?>> registeredEndpoints = new HashSet<Endpoint<?>>();
+	private final Set<Endpoint<?>> registeredEndpoints = new HashSet<Endpoint<?>>();
 
 	private volatile boolean autoStartup = true;
 
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMapping.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMapping.java
index 908b16c9eb..99420f240d 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMapping.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMapping.java
@@ -50,7 +50,7 @@ import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandl
 public class EndpointHandlerMapping extends RequestMappingHandlerMapping implements
 		ApplicationContextAware {
 
-	private Set<? extends MvcEndpoint> endpoints;
+	private final Set<? extends MvcEndpoint> endpoints;
 
 	private String prefix = "";
 
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/JolokiaMvcEndpoint.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/JolokiaMvcEndpoint.java
index 8f4d03edeb..e41182da9f 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/JolokiaMvcEndpoint.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/JolokiaMvcEndpoint.java
@@ -54,7 +54,7 @@ public class JolokiaMvcEndpoint implements MvcEndpoint, InitializingBean,
 
 	private boolean enabled = true;
 
-	private ServletWrappingController controller = new ServletWrappingController();
+	private final ServletWrappingController controller = new ServletWrappingController();
 
 	public JolokiaMvcEndpoint() {
 		this.path = "/jolokia";
@@ -123,7 +123,7 @@ public class JolokiaMvcEndpoint implements MvcEndpoint, InitializingBean,
 
 	private static class PathStripper extends HttpServletRequestWrapper {
 
-		private String path;
+		private final String path;
 
 		public PathStripper(HttpServletRequest request, String path) {
 			super(request);
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpoints.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpoints.java
index 5b7e329614..7880a44ba6 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpoints.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpoints.java
@@ -39,7 +39,7 @@ public class MvcEndpoints implements ApplicationContextAware, InitializingBean {
 
 	private ApplicationContext applicationContext;
 
-	private Set<MvcEndpoint> endpoints = new HashSet<MvcEndpoint>();
+	private final Set<MvcEndpoint> endpoints = new HashSet<MvcEndpoint>();
 
 	private Set<Class<?>> customTypes;
 
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepository.java
index d7012ea429..c1ce8697a6 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepository.java
@@ -36,9 +36,9 @@ import org.springframework.boot.actuate.metrics.writer.Delta;
 public class InMemoryMetricRepository implements MetricRepository, MultiMetricRepository,
 		PrefixMetricReader {
 
-	private SimpleInMemoryRepository<Metric<?>> metrics = new SimpleInMemoryRepository<Metric<?>>();
+	private final SimpleInMemoryRepository<Metric<?>> metrics = new SimpleInMemoryRepository<Metric<?>>();
 
-	private Collection<String> groups = new HashSet<String>();
+	private final Collection<String> groups = new HashSet<String>();
 
 	@Override
 	public void increment(Delta<?> delta) {
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMetricRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMetricRepository.java
index f8db3f35da..e819eaa172 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMetricRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMetricRepository.java
@@ -47,11 +47,11 @@ public class RedisMetricRepository implements MetricRepository {
 
 	private String keys = this.prefix + "keys";
 
-	private BoundZSetOperations<String, String> zSetOperations;
+	private final BoundZSetOperations<String, String> zSetOperations;
 
-	private RedisOperations<String, String> redisOperations;
+	private final RedisOperations<String, String> redisOperations;
 
-	private ValueOperations<String, Long> longOperations;
+	private final ValueOperations<String, Long> longOperations;
 
 	public RedisMetricRepository(RedisConnectionFactory redisConnectionFactory) {
 		Assert.notNull(redisConnectionFactory, "RedisConnectionFactory must not be null");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMultiMetricRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMultiMetricRepository.java
index fea6f68e3e..3067d0c6bc 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMultiMetricRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMultiMetricRepository.java
@@ -46,9 +46,9 @@ public class RedisMultiMetricRepository implements MultiMetricRepository {
 
 	private String keys = this.prefix + "keys";
 
-	private BoundZSetOperations<String, String> zSetOperations;
+	private final BoundZSetOperations<String, String> zSetOperations;
 
-	private RedisOperations<String, String> redisOperations;
+	private final RedisOperations<String, String> redisOperations;
 
 	public RedisMultiMetricRepository(RedisConnectionFactory redisConnectionFactory) {
 		Assert.notNull(redisConnectionFactory, "RedisConnectionFactory must not be null");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepository.java
index 3c09421f0f..b8f309c4ed 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepository.java
@@ -32,7 +32,7 @@ import org.springframework.boot.actuate.metrics.writer.MetricWriter;
  */
 public class InMemoryRichGaugeRepository implements RichGaugeRepository {
 
-	private SimpleInMemoryRepository<RichGauge> repository = new SimpleInMemoryRepository<RichGauge>();
+	private final SimpleInMemoryRepository<RichGauge> repository = new SimpleInMemoryRepository<RichGauge>();
 
 	@Override
 	public void increment(Delta<?> delta) {
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/util/SimpleInMemoryRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/util/SimpleInMemoryRepository.java
index a434a0b2e8..87ba26382a 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/util/SimpleInMemoryRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/util/SimpleInMemoryRepository.java
@@ -30,9 +30,9 @@ import java.util.concurrent.ConcurrentSkipListMap;
  */
 public class SimpleInMemoryRepository<T> {
 
-	private ConcurrentNavigableMap<String, T> values = new ConcurrentSkipListMap<String, T>();
+	private final ConcurrentNavigableMap<String, T> values = new ConcurrentSkipListMap<String, T>();
 
-	private ConcurrentMap<String, Object> locks = new ConcurrentHashMap<String, Object>();
+	private final ConcurrentMap<String, Object> locks = new ConcurrentHashMap<String, Object>();
 
 	public static interface Callback<T> {
 		T modify(T current);
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/CompositeMetricWriter.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/CompositeMetricWriter.java
index 881695a8fa..0e2186a9cf 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/CompositeMetricWriter.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/CompositeMetricWriter.java
@@ -29,7 +29,7 @@ import org.springframework.boot.actuate.metrics.Metric;
  */
 public class CompositeMetricWriter implements MetricWriter {
 
-	private List<MetricWriter> writers = new ArrayList<MetricWriter>();
+	private final List<MetricWriter> writers = new ArrayList<MetricWriter>();
 
 	public CompositeMetricWriter(MetricWriter... writers) {
 		for (MetricWriter writer : writers) {
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriter.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriter.java
index 2beb8c585e..210809a44b 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriter.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriter.java
@@ -31,7 +31,7 @@ public class MessageChannelMetricWriter implements MetricWriter {
 
 	private static final String METRIC_NAME = "metricName";
 
-	private String DELETE = "delete";
+	private final String DELETE = "delete";
 
 	private final MessageChannel channel;
 
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ManagementServerProperties.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ManagementServerProperties.java
index 483b7bd1f7..037617ca4e 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ManagementServerProperties.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ManagementServerProperties.java
@@ -42,7 +42,7 @@ public class ManagementServerProperties implements SecurityPrequisite {
 	@NotNull
 	private String contextPath = "";
 
-	private Security security = maybeCreateSecurity();
+	private final Security security = maybeCreateSecurity();
 
 	/**
 	 * Returns the management port or {@code null} if the
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ShellProperties.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ShellProperties.java
index 132bd2530d..c353db9a5e 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ShellProperties.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/properties/ShellProperties.java
@@ -57,9 +57,9 @@ public class ShellProperties {
 
 	private String[] disabledPlugins = new String[0];
 
-	private Ssh ssh = new Ssh();
+	private final Ssh ssh = new Ssh();
 
-	private Telnet telnet = new Telnet();
+	private final Telnet telnet = new Telnet();
 
 	public void setAuth(String auth) {
 		Assert.hasLength(auth, "Auth must not be empty");
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/InMemoryTraceRepository.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/InMemoryTraceRepository.java
index 1a9ce9ec7e..90de3d73ac 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/InMemoryTraceRepository.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/InMemoryTraceRepository.java
@@ -31,7 +31,7 @@ public class InMemoryTraceRepository implements TraceRepository {
 
 	private int capacity = 100;
 
-	private List<Trace> traces = new ArrayList<Trace>();
+	private final List<Trace> traces = new ArrayList<Trace>();
 
 	/**
 	 * @param capacity the capacity to set
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/Trace.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/Trace.java
index f797f32271..fbf4faaf42 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/Trace.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/Trace.java
@@ -29,9 +29,9 @@ import org.springframework.util.Assert;
  */
 public final class Trace {
 
-	private Date timestamp;
+	private final Date timestamp;
 
-	private Map<String, Object> info;
+	private final Map<String, Object> info;
 
 	public Trace(Date timestamp, Map<String, Object> info) {
 		super();
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/WebRequestTraceFilter.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/WebRequestTraceFilter.java
index 8ddb0b5afa..2fe115367e 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/WebRequestTraceFilter.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/WebRequestTraceFilter.java
@@ -55,7 +55,7 @@ public class WebRequestTraceFilter implements Filter, Ordered {
 
 	private int order = Integer.MAX_VALUE;
 
-	private ObjectMapper objectMapper = new ObjectMapper();
+	private final ObjectMapper objectMapper = new ObjectMapper();
 
 	private BasicErrorController errorController;
 
diff --git a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/BasicErrorController.java b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/BasicErrorController.java
index 5067aaaacc..8fb01de0d3 100644
--- a/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/BasicErrorController.java
+++ b/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/BasicErrorController.java
@@ -51,7 +51,7 @@ public class BasicErrorController implements ErrorController {
 
 	private static final String ERROR_KEY = "error";
 
-	private Log logger = LogFactory.getLog(BasicErrorController.class);
+	private final Log logger = LogFactory.getLog(BasicErrorController.class);
 
 	@Value("${error.path:/error}")
 	private String errorPath;
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepositoryTests.java
index a6a9418391..8015a555e9 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepositoryTests.java
@@ -29,7 +29,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class InMemoryAuditEventRepositoryTests {
 
-	private InMemoryAuditEventRepository repository = new InMemoryAuditEventRepository();
+	private final InMemoryAuditEventRepository repository = new InMemoryAuditEventRepository();
 
 	@Test
 	public void testAddToCapacity() throws Exception {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java
index 7c0cd8c59e..2b02b9aabc 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java
@@ -56,7 +56,7 @@ import static org.junit.Assert.assertThat;
  */
 public class EndpointWebMvcAutoConfigurationTests {
 
-	private AnnotationConfigEmbeddedWebApplicationContext applicationContext = new AnnotationConfigEmbeddedWebApplicationContext();
+	private final AnnotationConfigEmbeddedWebApplicationContext applicationContext = new AnnotationConfigEmbeddedWebApplicationContext();
 
 	@After
 	public void close() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMappingTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMappingTests.java
index 9a01ba3b83..91c30a4133 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMappingTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/EndpointHandlerMappingTests.java
@@ -44,7 +44,7 @@ import static org.junit.Assert.assertThat;
  */
 public class EndpointHandlerMappingTests {
 
-	private StaticApplicationContext context = new StaticApplicationContext();
+	private final StaticApplicationContext context = new StaticApplicationContext();
 	private Method method;
 
 	@Before
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/health/SimpleHealthIndicatorTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/health/SimpleHealthIndicatorTests.java
index 2afa405d09..8ca89bcadf 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/health/SimpleHealthIndicatorTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/health/SimpleHealthIndicatorTests.java
@@ -40,7 +40,7 @@ import static org.mockito.Mockito.when;
  */
 public class SimpleHealthIndicatorTests {
 
-	private SimpleHealthIndicator indicator = new SimpleHealthIndicator();
+	private final SimpleHealthIndicator indicator = new SimpleHealthIndicator();
 	private DriverManagerDataSource dataSource;
 
 	@Before
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/MetricCopyExporterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/MetricCopyExporterTests.java
index 67a29e84b0..accd5d60ca 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/MetricCopyExporterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/MetricCopyExporterTests.java
@@ -29,9 +29,9 @@ import static org.junit.Assert.assertEquals;
  */
 public class MetricCopyExporterTests {
 
-	private InMemoryMetricRepository writer = new InMemoryMetricRepository();
-	private InMemoryMetricRepository reader = new InMemoryMetricRepository();
-	private MetricCopyExporter exporter = new MetricCopyExporter(this.reader, this.writer);
+	private final InMemoryMetricRepository writer = new InMemoryMetricRepository();
+	private final InMemoryMetricRepository reader = new InMemoryMetricRepository();
+	private final MetricCopyExporter exporter = new MetricCopyExporter(this.reader, this.writer);
 
 	@Test
 	public void export() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/PrefixMetricGroupExporterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/PrefixMetricGroupExporterTests.java
index 54b694404c..5f41f3af79 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/PrefixMetricGroupExporterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/PrefixMetricGroupExporterTests.java
@@ -32,11 +32,11 @@ import static org.junit.Assert.assertEquals;
  */
 public class PrefixMetricGroupExporterTests {
 
-	private InMemoryMetricRepository reader = new InMemoryMetricRepository();
+	private final InMemoryMetricRepository reader = new InMemoryMetricRepository();
 
-	private InMemoryMetricRepository writer = new InMemoryMetricRepository();
+	private final InMemoryMetricRepository writer = new InMemoryMetricRepository();
 
-	private PrefixMetricGroupExporter exporter = new PrefixMetricGroupExporter(
+	private final PrefixMetricGroupExporter exporter = new PrefixMetricGroupExporter(
 			this.reader, this.writer);
 
 	@Test
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/RichGaugeExporterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/RichGaugeExporterTests.java
index ae30c5275b..4735af10e7 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/RichGaugeExporterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/export/RichGaugeExporterTests.java
@@ -29,9 +29,9 @@ import static org.junit.Assert.assertEquals;
  */
 public class RichGaugeExporterTests {
 
-	private InMemoryRichGaugeRepository reader = new InMemoryRichGaugeRepository();
-	private InMemoryMetricRepository writer = new InMemoryMetricRepository();
-	private RichGaugeExporter exporter = new RichGaugeExporter(this.reader, this.writer);
+	private final InMemoryRichGaugeRepository reader = new InMemoryRichGaugeRepository();
+	private final InMemoryMetricRepository writer = new InMemoryMetricRepository();
+	private final RichGaugeExporter exporter = new RichGaugeExporter(this.reader, this.writer);
 
 	@Test
 	public void prefixedMetricsCopied() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepositoryTests.java
index 4cb3e3bd50..dbc20a4b1a 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryMetricRepositoryTests.java
@@ -29,7 +29,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class InMemoryMetricRepositoryTests {
 
-	private InMemoryMetricRepository repository = new InMemoryMetricRepository();
+	private final InMemoryMetricRepository repository = new InMemoryMetricRepository();
 
 	@Test
 	public void increment() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryPrefixMetricRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryPrefixMetricRepositoryTests.java
index 58f0dcc3e9..cbf3b99c04 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryPrefixMetricRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/InMemoryPrefixMetricRepositoryTests.java
@@ -31,7 +31,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class InMemoryPrefixMetricRepositoryTests {
 
-	private InMemoryMetricRepository repository = new InMemoryMetricRepository();
+	private final InMemoryMetricRepository repository = new InMemoryMetricRepository();
 
 	@Test
 	public void registeredPrefixCounted() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/redis/RedisServer.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/redis/RedisServer.java
index 2afaf2ab6c..003b5f91c3 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/redis/RedisServer.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/repository/redis/RedisServer.java
@@ -38,7 +38,7 @@ public class RedisServer implements TestRule {
 
 	protected LettuceConnectionFactory resource;
 
-	private String resourceDescription = "Redis ConnectionFactory";
+	private final String resourceDescription = "Redis ConnectionFactory";
 
 	private static final Log logger = LogFactory.getLog(RedisServer.class);
 
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepositoryTests.java
index ac8383977d..3b4a5f3b58 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/rich/InMemoryRichGaugeRepositoryTests.java
@@ -26,7 +26,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class InMemoryRichGaugeRepositoryTests {
 
-	private InMemoryRichGaugeRepository repository = new InMemoryRichGaugeRepository();
+	private final InMemoryRichGaugeRepository repository = new InMemoryRichGaugeRepository();
 
 	@Test
 	public void writeAndRead() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/util/InMemoryRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/util/InMemoryRepositoryTests.java
index b9e825a184..0349376bd3 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/util/InMemoryRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/util/InMemoryRepositoryTests.java
@@ -37,7 +37,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class InMemoryRepositoryTests {
 
-	private SimpleInMemoryRepository<String> repository = new SimpleInMemoryRepository<String>();
+	private final SimpleInMemoryRepository<String> repository = new SimpleInMemoryRepository<String>();
 
 	@Test
 	public void setAndGet() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/CodahaleMetricWriterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/CodahaleMetricWriterTests.java
index 150bed13ef..226f0fa676 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/CodahaleMetricWriterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/CodahaleMetricWriterTests.java
@@ -29,8 +29,8 @@ import static org.junit.Assert.assertEquals;
  */
 public class CodahaleMetricWriterTests {
 
-	private MetricRegistry registry = new MetricRegistry();
-	private CodahaleMetricWriter writer = new CodahaleMetricWriter(this.registry);
+	private final MetricRegistry registry = new MetricRegistry();
+	private final CodahaleMetricWriter writer = new CodahaleMetricWriter(this.registry);
 
 	@Test
 	public void incrementCounter() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultCounterServiceTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultCounterServiceTests.java
index 1ad200a94d..3000d387a0 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultCounterServiceTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultCounterServiceTests.java
@@ -28,9 +28,9 @@ import static org.mockito.Mockito.verify;
  */
 public class DefaultCounterServiceTests {
 
-	private MetricWriter repository = mock(MetricWriter.class);
+	private final MetricWriter repository = mock(MetricWriter.class);
 
-	private DefaultCounterService service = new DefaultCounterService(this.repository);
+	private final DefaultCounterService service = new DefaultCounterService(this.repository);
 
 	@Test
 	public void incrementPrependsCounter() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultGaugeServiceTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultGaugeServiceTests.java
index 61dd5e99a9..39e75c8755 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultGaugeServiceTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/DefaultGaugeServiceTests.java
@@ -29,9 +29,9 @@ import static org.mockito.Mockito.verify;
  */
 public class DefaultGaugeServiceTests {
 
-	private MetricWriter repository = mock(MetricWriter.class);
+	private final MetricWriter repository = mock(MetricWriter.class);
 
-	private DefaultGaugeService service = new DefaultGaugeService(this.repository);
+	private final DefaultGaugeService service = new DefaultGaugeService(this.repository);
 
 	@Test
 	public void setPrependsGauge() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriterTests.java
index 9703878917..f169fa029f 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/writer/MessageChannelMetricWriterTests.java
@@ -30,9 +30,9 @@ import static org.mockito.Mockito.verify;
  */
 public class MessageChannelMetricWriterTests {
 
-	private MessageChannel channel = mock(MessageChannel.class);
+	private final MessageChannel channel = mock(MessageChannel.class);
 
-	private MessageChannelMetricWriter observer = new MessageChannelMetricWriter(
+	private final MessageChannelMetricWriter observer = new MessageChannelMetricWriter(
 			this.channel);
 
 	@Test
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthenticationAuditListenerTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthenticationAuditListenerTests.java
index 4ad20c2ca1..3c0f2f3825 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthenticationAuditListenerTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthenticationAuditListenerTests.java
@@ -37,9 +37,9 @@ import static org.mockito.Mockito.verify;
  */
 public class AuthenticationAuditListenerTests {
 
-	private AuthenticationAuditListener listener = new AuthenticationAuditListener();
+	private final AuthenticationAuditListener listener = new AuthenticationAuditListener();
 
-	private ApplicationEventPublisher publisher = Mockito
+	private final ApplicationEventPublisher publisher = Mockito
 			.mock(ApplicationEventPublisher.class);
 
 	@Before
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthorizationAuditListenerTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthorizationAuditListenerTests.java
index 2f6bb01640..8112af6e82 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthorizationAuditListenerTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/security/AuthorizationAuditListenerTests.java
@@ -37,9 +37,9 @@ import static org.mockito.Mockito.verify;
  */
 public class AuthorizationAuditListenerTests {
 
-	private AuthorizationAuditListener listener = new AuthorizationAuditListener();
+	private final AuthorizationAuditListener listener = new AuthorizationAuditListener();
 
-	private ApplicationEventPublisher publisher = Mockito
+	private final ApplicationEventPublisher publisher = Mockito
 			.mock(ApplicationEventPublisher.class);
 
 	@Before
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/InMemoryTraceRepositoryTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/InMemoryTraceRepositoryTests.java
index d1ccbf9958..257a64a4d8 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/InMemoryTraceRepositoryTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/InMemoryTraceRepositoryTests.java
@@ -30,7 +30,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class InMemoryTraceRepositoryTests {
 
-	private InMemoryTraceRepository repository = new InMemoryTraceRepository();
+	private final InMemoryTraceRepository repository = new InMemoryTraceRepository();
 
 	@Test
 	public void capacityLimited() {
diff --git a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/WebRequestTraceFilterTests.java b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/WebRequestTraceFilterTests.java
index 69bd26b01c..0eb3815444 100644
--- a/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/WebRequestTraceFilterTests.java
+++ b/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/WebRequestTraceFilterTests.java
@@ -32,7 +32,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class WebRequestTraceFilterTests {
 
-	private WebRequestTraceFilter filter = new WebRequestTraceFilter(
+	private final WebRequestTraceFilter filter = new WebRequestTraceFilter(
 			new InMemoryTraceRepository());
 
 	@Test
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationReport.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationReport.java
index 2f83d71820..0d5fcd2f38 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationReport.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationReport.java
@@ -119,7 +119,7 @@ public class AutoConfigurationReport {
 	 */
 	public static class ConditionAndOutcomes implements Iterable<ConditionAndOutcome> {
 
-		private Set<ConditionAndOutcome> outcomes = new LinkedHashSet<ConditionAndOutcome>();
+		private final Set<ConditionAndOutcome> outcomes = new LinkedHashSet<ConditionAndOutcome>();
 
 		public void add(Condition condition, ConditionOutcome outcome) {
 			this.outcomes.add(new ConditionAndOutcome(condition, outcome));
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationSorter.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationSorter.java
index 93f6653124..eefbbdd2f4 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationSorter.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationSorter.java
@@ -47,7 +47,7 @@ import org.springframework.util.Assert;
  */
 class AutoConfigurationSorter {
 
-	private CachingMetadataReaderFactory metadataReaderFactory;
+	private final CachingMetadataReaderFactory metadataReaderFactory;
 
 	public AutoConfigurationSorter(ResourceLoader resourceLoader) {
 		Assert.notNull(resourceLoader, "ResourceLoader must not be null");
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/BasicBatchConfigurer.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/BasicBatchConfigurer.java
index 0fe2270477..3036489dfd 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/BasicBatchConfigurer.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/BasicBatchConfigurer.java
@@ -42,9 +42,9 @@ public class BasicBatchConfigurer implements BatchConfigurer {
 
 	private static Log logger = LogFactory.getLog(BasicBatchConfigurer.class);
 
-	private DataSource dataSource;
+	private final DataSource dataSource;
 
-	private EntityManagerFactory entityManagerFactory;
+	private final EntityManagerFactory entityManagerFactory;
 
 	private PlatformTransactionManager transactionManager;
 
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionEvent.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionEvent.java
index fde47f745d..9e704fb810 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionEvent.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionEvent.java
@@ -26,7 +26,7 @@ import org.springframework.context.ApplicationEvent;
  */
 public class JobExecutionEvent extends ApplicationEvent {
 
-	private JobExecution execution;
+	private final JobExecution execution;
 
 	/**
 	 * @param execution the job execution
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGenerator.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGenerator.java
index 351acb5930..1695c4056d 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGenerator.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGenerator.java
@@ -31,7 +31,7 @@ import org.springframework.context.ApplicationListener;
 public class JobExecutionExitCodeGenerator implements
 		ApplicationListener<JobExecutionEvent>, ExitCodeGenerator {
 
-	private List<JobExecution> executions = new ArrayList<JobExecution>();
+	private final List<JobExecution> executions = new ArrayList<JobExecution>();
 
 	@Override
 	public void onApplicationEvent(JobExecutionEvent event) {
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobLauncherCommandLineRunner.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobLauncherCommandLineRunner.java
index 1ad46f7dc3..81ad93d6a4 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobLauncherCommandLineRunner.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobLauncherCommandLineRunner.java
@@ -53,7 +53,7 @@ public class JobLauncherCommandLineRunner implements CommandLineRunner,
 	private static Log logger = LogFactory.getLog(JobLauncherCommandLineRunner.class);
 
 	@Autowired(required = false)
-	private JobParametersConverter converter = new DefaultJobParametersConverter();
+	private final JobParametersConverter converter = new DefaultJobParametersConverter();
 
 	@Autowired
 	private JobLauncher jobLauncher;
@@ -64,7 +64,7 @@ public class JobLauncherCommandLineRunner implements CommandLineRunner,
 	private String jobName;
 
 	@Autowired(required = false)
-	private Collection<Job> jobs = Collections.emptySet();
+	private final Collection<Job> jobs = Collections.emptySet();
 
 	private ApplicationEventPublisher publisher;
 
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
index 419984c2a9..11cb54f53c 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
@@ -180,13 +180,13 @@ class OnBeanCondition extends SpringBootCondition implements ConfigurationCondit
 
 	private static class BeanSearchSpec {
 
-		private List<String> names = new ArrayList<String>();
+		private final List<String> names = new ArrayList<String>();
 
-		private List<String> types = new ArrayList<String>();
+		private final List<String> types = new ArrayList<String>();
 
-		private List<String> annotations = new ArrayList<String>();
+		private final List<String> annotations = new ArrayList<String>();
 
-		private SearchStrategy strategy;
+		private final SearchStrategy strategy;
 
 		public BeanSearchSpec(ConditionContext context, AnnotatedTypeMetadata metadata,
 				Class<?> annotationType) {
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnResourceCondition.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnResourceCondition.java
index 149e1049a9..b220bd0e8a 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnResourceCondition.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnResourceCondition.java
@@ -35,7 +35,7 @@ import org.springframework.util.MultiValueMap;
  */
 class OnResourceCondition extends SpringBootCondition {
 
-	private ResourceLoader defaultResourceLoader = new DefaultResourceLoader();
+	private final ResourceLoader defaultResourceLoader = new DefaultResourceLoader();
 
 	@Override
 	public ConditionOutcome getMatchOutcome(ConditionContext context,
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java
index 91495b87b4..eff59011ac 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java
@@ -252,7 +252,7 @@ public class DataSourceAutoConfiguration implements EnvironmentAware {
 	 */
 	static class BasicDatabaseCondition extends NonEmbeddedDatabaseCondition {
 
-		private Condition tomcatCondition = new TomcatDatabaseCondition();
+		private final Condition tomcatCondition = new TomcatDatabaseCondition();
 
 		@Override
 		protected String getDataSourceClassName() {
@@ -286,9 +286,9 @@ public class DataSourceAutoConfiguration implements EnvironmentAware {
 	 */
 	static class EmbeddedDatabaseCondition extends SpringBootCondition {
 
-		private SpringBootCondition tomcatCondition = new TomcatDatabaseCondition();
+		private final SpringBootCondition tomcatCondition = new TomcatDatabaseCondition();
 
-		private SpringBootCondition dbcpCondition = new BasicDatabaseCondition();
+		private final SpringBootCondition dbcpCondition = new BasicDatabaseCondition();
 
 		@Override
 		public ConditionOutcome getMatchOutcome(ConditionContext context,
@@ -311,11 +311,11 @@ public class DataSourceAutoConfiguration implements EnvironmentAware {
 	 */
 	static class DatabaseCondition extends SpringBootCondition {
 
-		private SpringBootCondition tomcatCondition = new TomcatDatabaseCondition();
+		private final SpringBootCondition tomcatCondition = new TomcatDatabaseCondition();
 
-		private SpringBootCondition dbcpCondition = new BasicDatabaseCondition();
+		private final SpringBootCondition dbcpCondition = new BasicDatabaseCondition();
 
-		private SpringBootCondition embeddedCondition = new EmbeddedDatabaseCondition();
+		private final SpringBootCondition embeddedCondition = new EmbeddedDatabaseCondition();
 
 		@Override
 		public ConditionOutcome getMatchOutcome(ConditionContext context,
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
index 55bf167fa2..41f23da1f0 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
@@ -40,13 +40,13 @@ public class SecurityProperties implements SecurityPrequisite {
 
 	private Basic basic = new Basic();
 
-	private Headers headers = new Headers();
+	private final Headers headers = new Headers();
 
 	private SessionCreationPolicy sessions = SessionCreationPolicy.STATELESS;
 
 	private List<String> ignored = new ArrayList<String>();
 
-	private User user = new User();
+	private final User user = new User();
 
 	public Headers getHeaders() {
 		return this.headers;
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
index 4d0c782849..df6e8c0a17 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
@@ -63,7 +63,7 @@ public class ThymeleafAutoConfiguration {
 	public static class DefaultTemplateResolverConfiguration implements EnvironmentAware {
 
 		@Autowired
-		private ResourceLoader resourceLoader = new DefaultResourceLoader();
+		private final ResourceLoader resourceLoader = new DefaultResourceLoader();
 
 		private RelaxedPropertyResolver environment;
 
@@ -108,10 +108,10 @@ public class ThymeleafAutoConfiguration {
 	protected static class ThymeleafDefaultConfiguration {
 
 		@Autowired
-		private Collection<ITemplateResolver> templateResolvers = Collections.emptySet();
+		private final Collection<ITemplateResolver> templateResolvers = Collections.emptySet();
 
 		@Autowired(required = false)
-		private Collection<IDialect> dialects = Collections.emptySet();
+		private final Collection<IDialect> dialects = Collections.emptySet();
 
 		@Bean
 		public SpringTemplateEngine templateEngine() {
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConverters.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConverters.java
index 1ea7f46973..afcae7fc4e 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConverters.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConverters.java
@@ -50,7 +50,7 @@ import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupp
  */
 public class HttpMessageConverters implements Iterable<HttpMessageConverter<?>> {
 
-	private List<HttpMessageConverter<?>> converters;
+	private final List<HttpMessageConverter<?>> converters;
 
 	/**
 	 * Create a new {@link HttpMessageConverters} instance with the specified additional
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConvertersAutoConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConvertersAutoConfiguration.java
index b38320aaea..591436fa40 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConvertersAutoConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/HttpMessageConvertersAutoConfiguration.java
@@ -50,7 +50,7 @@ import com.fasterxml.jackson.datatype.joda.JodaModule;
 public class HttpMessageConvertersAutoConfiguration {
 
 	@Autowired(required = false)
-	private List<HttpMessageConverter<?>> converters = Collections.emptyList();
+	private final List<HttpMessageConverter<?>> converters = Collections.emptyList();
 
 	@Bean
 	@ConditionalOnMissingBean
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java
index 7379bcb4c5..f820753cb7 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java
@@ -56,7 +56,7 @@ public class ServerProperties implements EmbeddedServletContainerCustomizer {
 	@NotNull
 	private String contextPath = "";
 
-	private Tomcat tomcat = new Tomcat();
+	private final Tomcat tomcat = new Tomcat();
 
 	public Tomcat getTomcat() {
 		return this.tomcat;
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/websocket/WebSocketAutoConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/websocket/WebSocketAutoConfiguration.java
index 8b9e15c159..fe1d51469c 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/websocket/WebSocketAutoConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/websocket/WebSocketAutoConfiguration.java
@@ -69,7 +69,7 @@ public class WebSocketAutoConfiguration {
 	protected static class WebSocketRegistrationConfiguration implements
 			BeanPostProcessor, BeanFactoryAware, WebSocketConfigurer {
 
-		private Map<String, WebSocketHandler> prefixes = new HashMap<String, WebSocketHandler>();
+		private final Map<String, WebSocketHandler> prefixes = new HashMap<String, WebSocketHandler>();
 
 		private ListableBeanFactory beanFactory;
 
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/PropertyPlaceholderAutoConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/PropertyPlaceholderAutoConfigurationTests.java
index cccb008c20..146694ad9a 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/PropertyPlaceholderAutoConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/PropertyPlaceholderAutoConfigurationTests.java
@@ -35,7 +35,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class PropertyPlaceholderAutoConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@After
 	public void close() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGeneratorTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGeneratorTests.java
index 3f9a75cd49..c2a2822f45 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGeneratorTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/batch/JobExecutionExitCodeGeneratorTests.java
@@ -29,7 +29,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class JobExecutionExitCodeGeneratorTests {
 
-	private JobExecutionExitCodeGenerator generator = new JobExecutionExitCodeGenerator();
+	private final JobExecutionExitCodeGenerator generator = new JobExecutionExitCodeGenerator();
 
 	@Test
 	public void testExitCodeForRunning() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnBeanTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnBeanTests.java
index fa31786529..49570d6d3f 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnBeanTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnBeanTests.java
@@ -37,7 +37,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnBeanTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testNameOnBeanCondition() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnClassTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnClassTests.java
index e27c7c1409..262b2f3046 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnClassTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnClassTests.java
@@ -34,7 +34,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnClassTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testVanillaOnClassCondition() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnExpressionTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnExpressionTests.java
index 6808488025..f2c02c2c7c 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnExpressionTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnExpressionTests.java
@@ -32,7 +32,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnExpressionTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testResourceExists() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanTests.java
index 1848afb127..6cdd22cacb 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanTests.java
@@ -41,7 +41,7 @@ import static org.junit.Assert.assertTrue;
 @SuppressWarnings("resource")
 public class ConditionalOnMissingBeanTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testNameOnMissingBeanCondition() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingClassTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingClassTests.java
index dc8d3bdf1b..b3c3fed613 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingClassTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingClassTests.java
@@ -32,7 +32,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnMissingClassTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testVanillaOnClassCondition() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnNotWebApplicationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnNotWebApplicationTests.java
index 78d2d4b051..8802df953e 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnNotWebApplicationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnNotWebApplicationTests.java
@@ -32,7 +32,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnNotWebApplicationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testWebApplication() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnResourceTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnResourceTests.java
index cadd95fece..f4384190fa 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnResourceTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnResourceTests.java
@@ -32,7 +32,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnResourceTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testResourceExists() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnWebApplicationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnWebApplicationTests.java
index 391d28df34..a4c566ee3f 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnWebApplicationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnWebApplicationTests.java
@@ -33,7 +33,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class ConditionalOnWebApplicationTests {
 
-	private AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
+	private final AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
 
 	@Test
 	public void testWebApplication() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/CommonsDataSourceConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/CommonsDataSourceConfigurationTests.java
index 1a75c527c2..358c76342d 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/CommonsDataSourceConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/CommonsDataSourceConfigurationTests.java
@@ -30,7 +30,7 @@ import static org.junit.Assert.assertNotNull;
  */
 public class CommonsDataSourceConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testDataSourceExists() throws Exception {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfigurationTests.java
index a4b1c736ee..0188d16df7 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfigurationTests.java
@@ -54,7 +54,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class DataSourceAutoConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testDefaultDataSourceExists() throws Exception {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceTransactionManagerAutoConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceTransactionManagerAutoConfigurationTests.java
index 6ac81d730a..f85e4be1ae 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceTransactionManagerAutoConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceTransactionManagerAutoConfigurationTests.java
@@ -33,7 +33,7 @@ import static org.junit.Assert.assertNotNull;
  */
 public class DataSourceTransactionManagerAutoConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void testDataSourceExists() throws Exception {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfigurationTests.java
index 721348e75f..d79f285fe8 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfigurationTests.java
@@ -38,7 +38,7 @@ import static org.junit.Assert.assertNotNull;
  */
 public class TomcatDataSourceConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@After
 	public void restore() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/reactor/ReactorAutoConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/reactor/ReactorAutoConfigurationTests.java
index 8de7a1f0bd..dd0b38d558 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/reactor/ReactorAutoConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/reactor/ReactorAutoConfigurationTests.java
@@ -28,7 +28,7 @@ import static org.junit.Assert.assertNotNull;
  */
 public class ReactorAutoConfigurationTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Test
 	public void reactorIsAvailable() {
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ServerPropertiesTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ServerPropertiesTests.java
index 1737446525..5524db4b4f 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ServerPropertiesTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ServerPropertiesTests.java
@@ -38,7 +38,7 @@ import static org.mockito.Mockito.verify;
  */
 public class ServerPropertiesTests {
 
-	private ServerProperties properties = new ServerProperties();
+	private final ServerProperties properties = new ServerProperties();
 
 	@Test
 	public void testAddressBinding() throws Exception {
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/OptionParsingCommand.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/OptionParsingCommand.java
index 769400ce52..8261eebfaa 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/OptionParsingCommand.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/OptionParsingCommand.java
@@ -27,7 +27,7 @@ import java.util.Collection;
  */
 public abstract class OptionParsingCommand extends AbstractCommand {
 
-	private OptionHandler handler;
+	private final OptionHandler handler;
 
 	protected OptionParsingCommand(String name, String description, OptionHandler handler) {
 		super(name, description);
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/SourceOptions.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/SourceOptions.java
index 22a4f634a6..00212f7944 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/SourceOptions.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/SourceOptions.java
@@ -33,9 +33,9 @@ import org.springframework.boot.cli.util.ResourceUtils;
  */
 public class SourceOptions {
 
-	private List<String> sources;
+	private final List<String> sources;
 
-	private List<?> args;
+	private final List<?> args;
 
 	/**
 	 * Create a new {@link SourceOptions} instance.
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/AnsiString.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/AnsiString.java
index 1a0b3f43cf..580691687e 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/AnsiString.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/AnsiString.java
@@ -30,7 +30,7 @@ class AnsiString {
 
 	private final Terminal terminal;
 
-	private StringBuilder value = new StringBuilder();
+	private final StringBuilder value = new StringBuilder();
 
 	/**
 	 * Create a new {@link AnsiString} for the given {@link Terminal}.
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/CommandCompleter.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/CommandCompleter.java
index 6ac752c0e3..e169da6cc5 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/CommandCompleter.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/CommandCompleter.java
@@ -44,9 +44,9 @@ public class CommandCompleter extends StringsCompleter {
 
 	private final Map<String, Completer> commandCompleters = new HashMap<String, Completer>();
 
-	private List<Command> commands = new ArrayList<Command>();
+	private final List<Command> commands = new ArrayList<Command>();
 
-	private ConsoleReader console;
+	private final ConsoleReader console;
 
 	public CommandCompleter(ConsoleReader consoleReader,
 			ArgumentDelimiter argumentDelimiter, Iterable<Command> commands) {
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/Shell.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/Shell.java
index e0f67fe702..f30cc944ca 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/Shell.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/Shell.java
@@ -62,13 +62,13 @@ public class Shell {
 
 	private static final String DEFAULT_PROMPT = "$ ";
 
-	private ShellCommandRunner commandRunner;
+	private final ShellCommandRunner commandRunner;
 
-	private ConsoleReader consoleReader;
+	private final ConsoleReader consoleReader;
 
-	private EscapeAwareWhiteSpaceArgumentDelimiter argumentDelimiter = new EscapeAwareWhiteSpaceArgumentDelimiter();
+	private final EscapeAwareWhiteSpaceArgumentDelimiter argumentDelimiter = new EscapeAwareWhiteSpaceArgumentDelimiter();
 
-	private Stack<String> prompts = new Stack<String>();
+	private final Stack<String> prompts = new Stack<String>();
 
 	/**
 	 * Create a new {@link Shell} instance.
diff --git a/spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/transformation/GroovyBeansTransformation.java b/spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/transformation/GroovyBeansTransformation.java
index 095bf6b190..82a0220047 100644
--- a/spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/transformation/GroovyBeansTransformation.java
+++ b/spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/transformation/GroovyBeansTransformation.java
@@ -65,7 +65,7 @@ public class GroovyBeansTransformation implements ASTTransformation {
 		private static final String SOURCE_INTERFACE = "org.springframework.boot.BeanDefinitionLoader.GroovyBeanDefinitionSource";
 		private static final String BEANS = "beans";
 		private final SourceUnit source;
-		private ClassNode classNode;
+		private final ClassNode classNode;
 		private boolean xformed = false;
 
 		public ClassVisitor(SourceUnit source, ClassNode classNode) {
diff --git a/spring-boot-cli/src/test/java/org/springframework/boot/cli/CliTester.java b/spring-boot-cli/src/test/java/org/springframework/boot/cli/CliTester.java
index 6fceb1e8f0..8bd6b39f9f 100644
--- a/spring-boot-cli/src/test/java/org/springframework/boot/cli/CliTester.java
+++ b/spring-boot-cli/src/test/java/org/springframework/boot/cli/CliTester.java
@@ -48,13 +48,13 @@ import org.springframework.boot.cli.util.OutputCapture;
  */
 public class CliTester implements TestRule {
 
-	private OutputCapture outputCapture = new OutputCapture();
+	private final OutputCapture outputCapture = new OutputCapture();
 
 	private long timeout = TimeUnit.MINUTES.toMillis(6);
 
-	private List<AbstractCommand> commands = new ArrayList<AbstractCommand>();
+	private final List<AbstractCommand> commands = new ArrayList<AbstractCommand>();
 
-	private String prefix;
+	private final String prefix;
 
 	public CliTester(String prefix) {
 		this.prefix = prefix;
diff --git a/spring-boot-cli/src/test/java/org/springframework/boot/cli/CommandRunnerTests.java b/spring-boot-cli/src/test/java/org/springframework/boot/cli/CommandRunnerTests.java
index 2704d32b0f..097b8bf2b2 100644
--- a/spring-boot-cli/src/test/java/org/springframework/boot/cli/CommandRunnerTests.java
+++ b/spring-boot-cli/src/test/java/org/springframework/boot/cli/CommandRunnerTests.java
@@ -56,7 +56,7 @@ public class CommandRunnerTests {
 	@Mock
 	private Command anotherCommand;
 
-	private Set<Call> calls = EnumSet.noneOf(Call.class);
+	private final Set<Call> calls = EnumSet.noneOf(Call.class);
 
 	private ClassLoader loader;
 
diff --git a/spring-boot-cli/src/test/java/org/springframework/boot/cli/command/shell/EscapeAwareWhiteSpaceArgumentDelimiterTests.java b/spring-boot-cli/src/test/java/org/springframework/boot/cli/command/shell/EscapeAwareWhiteSpaceArgumentDelimiterTests.java
index 536ef394f4..4fe0a32ca2 100644
--- a/spring-boot-cli/src/test/java/org/springframework/boot/cli/command/shell/EscapeAwareWhiteSpaceArgumentDelimiterTests.java
+++ b/spring-boot-cli/src/test/java/org/springframework/boot/cli/command/shell/EscapeAwareWhiteSpaceArgumentDelimiterTests.java
@@ -30,7 +30,7 @@ import static org.junit.Assert.assertThat;
  */
 public class EscapeAwareWhiteSpaceArgumentDelimiterTests {
 
-	private EscapeAwareWhiteSpaceArgumentDelimiter delimiter = new EscapeAwareWhiteSpaceArgumentDelimiter();
+	private final EscapeAwareWhiteSpaceArgumentDelimiter delimiter = new EscapeAwareWhiteSpaceArgumentDelimiter();
 
 	@Test
 	public void simple() throws Exception {
diff --git a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/HotelSummary.java b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/HotelSummary.java
index 3af7204e71..fabe2daeb6 100644
--- a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/HotelSummary.java
+++ b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/HotelSummary.java
@@ -28,13 +28,13 @@ public class HotelSummary implements Serializable {
 	private static final MathContext MATH_CONTEXT = new MathContext(2,
 			RoundingMode.HALF_UP);
 
-	private City city;
+	private final City city;
 
-	private String name;
+	private final String name;
 
-	private Double averageRating;
+	private final Double averageRating;
 
-	private Integer averageRatingRounded;
+	private final Integer averageRatingRounded;
 
 	public HotelSummary(City city, String name, Double averageRating) {
 		this.city = city;
diff --git a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/RatingCount.java b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/RatingCount.java
index 5b1471eb22..e81c7ae1fb 100644
--- a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/RatingCount.java
+++ b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/RatingCount.java
@@ -22,9 +22,9 @@ public class RatingCount implements Serializable {
 
 	private static final long serialVersionUID = 1L;
 
-	private Rating rating;
+	private final Rating rating;
 
-	private long count;
+	private final long count;
 
 	public RatingCount(Rating rating, long count) {
 		this.rating = rating;
diff --git a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/service/HotelServiceImpl.java b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/service/HotelServiceImpl.java
index 83c7461181..e3ea7f0d65 100644
--- a/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/service/HotelServiceImpl.java
+++ b/spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/service/HotelServiceImpl.java
@@ -82,7 +82,7 @@ class HotelServiceImpl implements HotelService {
 
 	private static class ReviewsSummaryImpl implements ReviewsSummary {
 
-		private Map<Rating, Long> ratingCount;
+		private final Map<Rating, Long> ratingCount;
 
 		public ReviewsSummaryImpl(List<RatingCount> ratingCounts) {
 			this.ratingCount = new HashMap<Rating, Long>();
diff --git a/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/InMemoryMessageRespository.java b/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/InMemoryMessageRespository.java
index 074a961167..b112448c92 100644
--- a/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/InMemoryMessageRespository.java
+++ b/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/InMemoryMessageRespository.java
@@ -26,7 +26,7 @@ import java.util.concurrent.atomic.AtomicLong;
 public class InMemoryMessageRespository implements MessageRepository {
 
 	private static AtomicLong counter = new AtomicLong();
-	private ConcurrentMap<Long, Message> messages = new ConcurrentHashMap<Long, Message>();
+	private final ConcurrentMap<Long, Message> messages = new ConcurrentHashMap<Long, Message>();
 
 	@Override
 	public Iterable<Message> findAll() {
diff --git a/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/mvc/MessageController.java b/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/mvc/MessageController.java
index d0f8cc0226..aacd5c78e0 100644
--- a/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/mvc/MessageController.java
+++ b/spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/mvc/MessageController.java
@@ -34,7 +34,7 @@ import sample.ui.MessageRepository;
 @Controller
 @RequestMapping("/")
 public class MessageController {
-	private MessageRepository messageRepository;
+	private final MessageRepository messageRepository;
 
 	@Autowired
 	public MessageController(MessageRepository messageRepository) {
diff --git a/spring-boot-samples/spring-boot-sample-websocket/src/main/java/samples/websocket/client/SimpleClientWebSocketHandler.java b/spring-boot-samples/spring-boot-sample-websocket/src/main/java/samples/websocket/client/SimpleClientWebSocketHandler.java
index 0aa8a9488e..1b3dc4ef89 100644
--- a/spring-boot-samples/spring-boot-sample-websocket/src/main/java/samples/websocket/client/SimpleClientWebSocketHandler.java
+++ b/spring-boot-samples/spring-boot-sample-websocket/src/main/java/samples/websocket/client/SimpleClientWebSocketHandler.java
@@ -31,7 +31,7 @@ public class SimpleClientWebSocketHandler extends TextWebSocketHandler {
 
 	private final GreetingService greetingService;
 
-	private CountDownLatch latch;
+	private final CountDownLatch latch;
 
 	@Autowired
 	public SimpleClientWebSocketHandler(GreetingService greetingService,
diff --git a/spring-boot-samples/spring-boot-sample-websocket/src/test/java/samples/websocket/echo/SampleWebSocketsApplicationTests.java b/spring-boot-samples/spring-boot-sample-websocket/src/test/java/samples/websocket/echo/SampleWebSocketsApplicationTests.java
index 36a783aefb..788e015f3f 100644
--- a/spring-boot-samples/spring-boot-sample-websocket/src/test/java/samples/websocket/echo/SampleWebSocketsApplicationTests.java
+++ b/spring-boot-samples/spring-boot-sample-websocket/src/test/java/samples/websocket/echo/SampleWebSocketsApplicationTests.java
@@ -83,7 +83,7 @@ public class SampleWebSocketsApplicationTests {
 	@Configuration
 	static class ClientConfiguration implements CommandLineRunner {
 
-		private CountDownLatch latch = new CountDownLatch(1);
+		private final CountDownLatch latch = new CountDownLatch(1);
 
 		@Override
 		public void run(String... args) throws Exception {
diff --git a/spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/JarWriter.java b/spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/JarWriter.java
index 60f90fd591..8af0572062 100644
--- a/spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/JarWriter.java
+++ b/spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/JarWriter.java
@@ -222,7 +222,7 @@ class JarWriter {
 
 		private static final byte[] ZIP_HEADER = new byte[] { 0x50, 0x4b, 0x03, 0x04 };
 
-		private byte[] header;
+		private final byte[] header;
 
 		private ByteArrayInputStream headerStream;
 
diff --git a/spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/TestJarFile.java b/spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/TestJarFile.java
index 7e42d96fef..a20671d726 100644
--- a/spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/TestJarFile.java
+++ b/spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/TestJarFile.java
@@ -36,9 +36,9 @@ public class TestJarFile {
 
 	private final byte[] buffer = new byte[4096];
 
-	private TemporaryFolder temporaryFolder;
+	private final TemporaryFolder temporaryFolder;
 
-	private File jarSource;
+	private final File jarSource;
 
 	public TestJarFile(TemporaryFolder temporaryFolder) throws IOException {
 		this.temporaryFolder = temporaryFolder;
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/MainMethodRunner.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/MainMethodRunner.java
index 3977a21172..fcd164a7e8 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/MainMethodRunner.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/MainMethodRunner.java
@@ -26,9 +26,9 @@ import java.lang.reflect.Method;
  */
 public class MainMethodRunner implements Runnable {
 
-	private String mainClassName;
+	private final String mainClassName;
 
-	private String[] args;
+	private final String[] args;
 
 	/**
 	 * Create a new {@link MainMethodRunner} instance.
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/PropertiesLauncher.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/PropertiesLauncher.java
index dfff61afae..a40b62ccbd 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/PropertiesLauncher.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/PropertiesLauncher.java
@@ -76,7 +76,7 @@ import org.springframework.boot.loader.util.SystemPropertyUtils;
  */
 public class PropertiesLauncher extends Launcher {
 
-	private Logger logger = Logger.getLogger(Launcher.class.getName());
+	private final Logger logger = Logger.getLogger(Launcher.class.getName());
 
 	/**
 	 * Properties key for main class
@@ -125,7 +125,7 @@ public class PropertiesLauncher extends Launcher {
 
 	private List<String> paths = new ArrayList<String>(DEFAULT_PATHS);
 
-	private Properties properties = new Properties();
+	private final Properties properties = new Properties();
 
 	public PropertiesLauncher() {
 		if (!isDebug()) {
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/ExplodedArchive.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/ExplodedArchive.java
index df3080ae52..763a34f97f 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/ExplodedArchive.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/ExplodedArchive.java
@@ -50,7 +50,7 @@ public class ExplodedArchive extends Archive {
 	private static final AsciiBytes MANIFEST_ENTRY_NAME = new AsciiBytes(
 			"META-INF/MANIFEST.MF");
 
-	private File root;
+	private final File root;
 
 	private Map<AsciiBytes, Entry> entries = new LinkedHashMap<AsciiBytes, Entry>();
 
@@ -200,7 +200,7 @@ public class ExplodedArchive extends Archive {
 	 */
 	private static class FileNotFoundURLConnection extends URLConnection {
 
-		private String name;
+		private final String name;
 
 		public FileNotFoundURLConnection(URL url, String name) {
 			super(url);
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/FilteredArchive.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/FilteredArchive.java
index 4ed025a9b4..7e4d6e4848 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/FilteredArchive.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/archive/FilteredArchive.java
@@ -34,9 +34,9 @@ import org.springframework.boot.loader.AsciiBytes;
  */
 public class FilteredArchive extends Archive {
 
-	private Archive parent;
+	private final Archive parent;
 
-	private EntryFilter filter;
+	private final EntryFilter filter;
 
 	public FilteredArchive(Archive parent, EntryFilter filter) {
 		this.parent = parent;
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/data/RandomAccessDataFile.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/data/RandomAccessDataFile.java
index d09d88b290..492b81b543 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/data/RandomAccessDataFile.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/data/RandomAccessDataFile.java
@@ -229,7 +229,7 @@ public class RandomAccessDataFile implements RandomAccessData {
 	 */
 	private class FilePool {
 
-		private int size;
+		private final int size;
 
 		private final Semaphore available;
 
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarEntryData.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarEntryData.java
index 455143f1bb..01a68eda0b 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarEntryData.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarEntryData.java
@@ -39,7 +39,7 @@ public final class JarEntryData {
 
 	private final JarFile source;
 
-	private byte[] header;
+	private final byte[] header;
 
 	private AsciiBytes name;
 
@@ -47,7 +47,7 @@ public final class JarEntryData {
 
 	private final AsciiBytes comment;
 
-	private long localHeaderOffset;
+	private final long localHeaderOffset;
 
 	private RandomAccessData data;
 
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java
index ba7a08da8c..fec690ba44 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java
@@ -65,7 +65,7 @@ public class JarFile extends java.util.jar.JarFile implements Iterable<JarEntryD
 
 	private final RandomAccessDataFile rootFile;
 
-	private RandomAccessData data;
+	private final RandomAccessData data;
 
 	private final String name;
 
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
index b97edfefc8..6f99de4966 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
@@ -33,7 +33,7 @@ class JarURLConnection extends java.net.JarURLConnection {
 
 	private static final String JAR_URL_PREFIX = "jar:file:";
 
-	private JarFile jarFile;
+	private final JarFile jarFile;
 
 	private JarEntryData jarEntryData;
 
diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLStreamHandler.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLStreamHandler.java
index 58c7e7ea05..375f3db431 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLStreamHandler.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLStreamHandler.java
@@ -28,7 +28,7 @@ import java.net.URLStreamHandler;
  */
 class JarURLStreamHandler extends URLStreamHandler {
 
-	private JarFile jarFile;
+	private final JarFile jarFile;
 
 	public JarURLStreamHandler(JarFile jarFile) {
 		this.jarFile = jarFile;
diff --git a/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/ByteArrayStartsWith.java b/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/ByteArrayStartsWith.java
index 7f8830b4e5..e0bca9c955 100644
--- a/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/ByteArrayStartsWith.java
+++ b/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/ByteArrayStartsWith.java
@@ -26,7 +26,7 @@ import org.hamcrest.TypeSafeMatcher;
  */
 public class ByteArrayStartsWith extends TypeSafeMatcher<byte[]> {
 
-	private byte[] bytes;
+	private final byte[] bytes;
 
 	public ByteArrayStartsWith(byte[] bytes) {
 		this.bytes = bytes;
diff --git a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/PropertiesMergingResourceTransformer.java b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/PropertiesMergingResourceTransformer.java
index 1194c0363e..e99ea84d0c 100644
--- a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/PropertiesMergingResourceTransformer.java
+++ b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/PropertiesMergingResourceTransformer.java
@@ -38,7 +38,7 @@ public class PropertiesMergingResourceTransformer implements ResourceTransformer
 	// Set this in pom configuration with <resource>...</resource>
 	private String resource;
 
-	private Properties data = new Properties();
+	private final Properties data = new Properties();
 
 	/**
 	 * @return the data the properties being merged
diff --git a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RepackageMojo.java b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RepackageMojo.java
index de66230cf5..36fa4cc18e 100644
--- a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RepackageMojo.java
+++ b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RepackageMojo.java
@@ -150,7 +150,7 @@ public class RepackageMojo extends AbstractMojo {
 	public static enum LayoutType {
 		JAR(new Layouts.Jar()), WAR(new Layouts.War()), ZIP(new Layouts.Expanded()), DIR(
 				new Layouts.Expanded()), NONE(new Layouts.None());
-		private Layout layout;
+		private final Layout layout;
 
 		public Layout layout() {
 			return this.layout;
diff --git a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RunMojo.java b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RunMojo.java
index 323fabf559..00375d8f70 100644
--- a/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RunMojo.java
+++ b/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RunMojo.java
@@ -228,8 +228,8 @@ public class RunMojo extends AbstractMojo {
 	 */
 	class LaunchRunner implements Runnable {
 
-		private String startClassName;
-		private String[] args;
+		private final String startClassName;
+		private final String[] args;
 
 		public LaunchRunner(String startClassName, String... args) {
 			this.startClassName = startClassName;
diff --git a/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/PropertiesMergingResourceTransformerTests.java b/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/PropertiesMergingResourceTransformerTests.java
index 818ef10fbf..02ac1326ed 100644
--- a/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/PropertiesMergingResourceTransformerTests.java
+++ b/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/PropertiesMergingResourceTransformerTests.java
@@ -34,7 +34,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class PropertiesMergingResourceTransformerTests {
 
-	private PropertiesMergingResourceTransformer transformer = new PropertiesMergingResourceTransformer();
+	private final PropertiesMergingResourceTransformer transformer = new PropertiesMergingResourceTransformer();
 
 	@Test
 	public void testProcess() throws Exception {
diff --git a/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/Verify.java b/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/Verify.java
index dd7e879cb2..84a3ff75e2 100644
--- a/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/Verify.java
+++ b/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/Verify.java
@@ -52,7 +52,7 @@ public class Verify {
 
 	private static abstract class AbstractArchiveVerification {
 
-		private File file;
+		private final File file;
 
 		public AbstractArchiveVerification(File file) {
 			this.file = file;
@@ -98,7 +98,7 @@ public class Verify {
 
 	private static class JarArchiveVerification extends AbstractArchiveVerification {
 
-		private String main;
+		private final String main;
 
 		public JarArchiveVerification(File file, String main) {
 			super(file);
diff --git a/spring-boot/src/main/java/org/springframework/boot/BeanDefinitionLoader.java b/spring-boot/src/main/java/org/springframework/boot/BeanDefinitionLoader.java
index fff74ab6ab..bef13950b9 100644
--- a/spring-boot/src/main/java/org/springframework/boot/BeanDefinitionLoader.java
+++ b/spring-boot/src/main/java/org/springframework/boot/BeanDefinitionLoader.java
@@ -56,15 +56,15 @@ class BeanDefinitionLoader {
 
 	private static final ResourceLoader DEFAULT_RESOURCE_LOADER = new PathMatchingResourcePatternResolver();
 
-	private Object[] sources;
+	private final Object[] sources;
 
-	private AnnotatedBeanDefinitionReader annotatedReader;
+	private final AnnotatedBeanDefinitionReader annotatedReader;
 
-	private XmlBeanDefinitionReader xmlReader;
+	private final XmlBeanDefinitionReader xmlReader;
 
 	private GroovyBeanDefinitionReader groovyReader;
 
-	private ClassPathBeanDefinitionScanner scanner;
+	private final ClassPathBeanDefinitionScanner scanner;
 
 	private ResourceLoader resourceLoader;
 
@@ -286,7 +286,7 @@ class BeanDefinitionLoader {
 	 */
 	private static class ClassExcludeFilter extends AbstractTypeHierarchyTraversingFilter {
 
-		private Set<String> classNames = new HashSet<String>();
+		private final Set<String> classNames = new HashSet<String>();
 
 		public ClassExcludeFilter(Object... sources) {
 			super(false, false);
diff --git a/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java b/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java
index 6e6c285d50..fec88304b3 100644
--- a/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java
+++ b/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java
@@ -157,7 +157,7 @@ public class SpringApplication {
 
 	private final Log log = LogFactory.getLog(getClass());
 
-	private Set<Object> sources = new LinkedHashSet<Object>();
+	private final Set<Object> sources = new LinkedHashSet<Object>();
 
 	private Class<?> mainApplicationClass;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationBeforeRefreshEvent.java b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationBeforeRefreshEvent.java
index 449fee45db..25e14e4acd 100644
--- a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationBeforeRefreshEvent.java
+++ b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationBeforeRefreshEvent.java
@@ -30,8 +30,8 @@ import org.springframework.core.env.Environment;
  */
 public class SpringApplicationBeforeRefreshEvent extends ApplicationEvent {
 
-	private String[] args;
-	private ConfigurableApplicationContext context;
+	private final String[] args;
+	private final ConfigurableApplicationContext context;
 
 	/**
 	 * @param springApplication the current application
diff --git a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationEnvironmentAvailableEvent.java b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationEnvironmentAvailableEvent.java
index ac9e80be13..f9e904becb 100644
--- a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationEnvironmentAvailableEvent.java
+++ b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationEnvironmentAvailableEvent.java
@@ -28,8 +28,8 @@ import org.springframework.core.env.Environment;
  */
 public class SpringApplicationEnvironmentAvailableEvent extends ApplicationEvent {
 
-	private ConfigurableEnvironment environment;
-	private String[] args;
+	private final ConfigurableEnvironment environment;
+	private final String[] args;
 
 	/**
 	 * @param springApplication the current application
diff --git a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationErrorEvent.java b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationErrorEvent.java
index 6c9e14f6ab..d7ead8bd5e 100644
--- a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationErrorEvent.java
+++ b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationErrorEvent.java
@@ -26,9 +26,9 @@ import org.springframework.context.ConfigurableApplicationContext;
  */
 public class SpringApplicationErrorEvent extends ApplicationEvent {
 
-	private String[] args;
-	private Throwable exception;
-	private ConfigurableApplicationContext context;
+	private final String[] args;
+	private final Throwable exception;
+	private final ConfigurableApplicationContext context;
 
 	/**
 	 * @param springApplication the current application
diff --git a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationStartEvent.java b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationStartEvent.java
index 4ea2d60097..9481e9b38b 100644
--- a/spring-boot/src/main/java/org/springframework/boot/SpringApplicationStartEvent.java
+++ b/spring-boot/src/main/java/org/springframework/boot/SpringApplicationStartEvent.java
@@ -32,7 +32,7 @@ import org.springframework.core.env.Environment;
  */
 public class SpringApplicationStartEvent extends ApplicationEvent {
 
-	private String[] args;
+	private final String[] args;
 
 	/**
 	 * @param springApplication the current application
diff --git a/spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java b/spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java
index 8ccf9ac5b5..487c3bd338 100644
--- a/spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java
+++ b/spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java
@@ -62,7 +62,7 @@ public class PropertiesConfigurationFactory<T> implements FactoryBean<T>,
 
 	private PropertySources propertySources;
 
-	private T target;
+	private final T target;
 
 	private Validator validator;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/bind/PropertySourcesPropertyValues.java b/spring-boot/src/main/java/org/springframework/boot/bind/PropertySourcesPropertyValues.java
index 618fead9a4..0bbbfcc8e3 100644
--- a/spring-boot/src/main/java/org/springframework/boot/bind/PropertySourcesPropertyValues.java
+++ b/spring-boot/src/main/java/org/springframework/boot/bind/PropertySourcesPropertyValues.java
@@ -41,11 +41,11 @@ import org.springframework.validation.DataBinder;
  */
 public class PropertySourcesPropertyValues implements PropertyValues {
 
-	private Map<String, PropertyValue> propertyValues = new ConcurrentHashMap<String, PropertyValue>();
+	private final Map<String, PropertyValue> propertyValues = new ConcurrentHashMap<String, PropertyValue>();
 
-	private PropertySources propertySources;
+	private final PropertySources propertySources;
 
-	private Collection<String> NON_ENUMERABLE_ENUMERABLES = Arrays.asList(
+	private final Collection<String> NON_ENUMERABLE_ENUMERABLES = Arrays.asList(
 			StandardEnvironment.SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME,
 			StandardEnvironment.SYSTEM_PROPERTIES_PROPERTY_SOURCE_NAME);
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/bind/RelaxedNames.java b/spring-boot/src/main/java/org/springframework/boot/bind/RelaxedNames.java
index 64a3cc37e8..8e1d88c472 100644
--- a/spring-boot/src/main/java/org/springframework/boot/bind/RelaxedNames.java
+++ b/spring-boot/src/main/java/org/springframework/boot/bind/RelaxedNames.java
@@ -34,7 +34,7 @@ public final class RelaxedNames implements Iterable<String> {
 
 	private final String name;
 
-	private Set<String> values = new LinkedHashSet<String>();
+	private final Set<String> values = new LinkedHashSet<String>();
 
 	/**
 	 * Create a new {@link RelaxedNames} instance.
diff --git a/spring-boot/src/main/java/org/springframework/boot/bind/YamlConfigurationFactory.java b/spring-boot/src/main/java/org/springframework/boot/bind/YamlConfigurationFactory.java
index 787d7c2574..e0614a9942 100644
--- a/spring-boot/src/main/java/org/springframework/boot/bind/YamlConfigurationFactory.java
+++ b/spring-boot/src/main/java/org/springframework/boot/bind/YamlConfigurationFactory.java
@@ -52,7 +52,7 @@ public class YamlConfigurationFactory<T> implements FactoryBean<T>, MessageSourc
 
 	private final Log logger = LogFactory.getLog(getClass());
 
-	private Class<?> type;
+	private final Class<?> type;
 
 	private boolean exceptionIfInvalid;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/builder/SpringApplicationBuilder.java b/spring-boot/src/main/java/org/springframework/boot/builder/SpringApplicationBuilder.java
index 9c39a7d143..7f0157adc1 100644
--- a/spring-boot/src/main/java/org/springframework/boot/builder/SpringApplicationBuilder.java
+++ b/spring-boot/src/main/java/org/springframework/boot/builder/SpringApplicationBuilder.java
@@ -63,17 +63,17 @@ import org.springframework.core.io.ResourceLoader;
  */
 public class SpringApplicationBuilder {
 
-	private SpringApplication application;
+	private final SpringApplication application;
 
 	private ConfigurableApplicationContext context;
 
 	private SpringApplicationBuilder parent;
 
-	private AtomicBoolean running = new AtomicBoolean(false);
+	private final AtomicBoolean running = new AtomicBoolean(false);
 
-	private Set<Object> sources = new LinkedHashSet<Object>();
+	private final Set<Object> sources = new LinkedHashSet<Object>();
 
-	private Map<String, Object> defaultProperties = new LinkedHashMap<String, Object>();
+	private final Map<String, Object> defaultProperties = new LinkedHashMap<String, Object>();
 
 	private ConfigurableEnvironment environment;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/config/ArrayDocumentMatcher.java b/spring-boot/src/main/java/org/springframework/boot/config/ArrayDocumentMatcher.java
index 492e19262e..58eaa54b56 100644
--- a/spring-boot/src/main/java/org/springframework/boot/config/ArrayDocumentMatcher.java
+++ b/spring-boot/src/main/java/org/springframework/boot/config/ArrayDocumentMatcher.java
@@ -32,9 +32,9 @@ import org.springframework.util.StringUtils;
  */
 public class ArrayDocumentMatcher implements DocumentMatcher {
 
-	private String key;
+	private final String key;
 
-	private String[] patterns;
+	private final String[] patterns;
 
 	public ArrayDocumentMatcher(final String key, final String... patterns) {
 		this.key = key;
diff --git a/spring-boot/src/main/java/org/springframework/boot/config/YamlPropertySourceLoader.java b/spring-boot/src/main/java/org/springframework/boot/config/YamlPropertySourceLoader.java
index 66d117b8e1..63e607aa48 100644
--- a/spring-boot/src/main/java/org/springframework/boot/config/YamlPropertySourceLoader.java
+++ b/spring-boot/src/main/java/org/springframework/boot/config/YamlPropertySourceLoader.java
@@ -35,7 +35,7 @@ import org.springframework.util.StringUtils;
  */
 public class YamlPropertySourceLoader extends PropertiesPropertySourceLoader {
 
-	private List<DocumentMatcher> matchers;
+	private final List<DocumentMatcher> matchers;
 
 	/**
 	 * Create a {@link YamlPropertySourceLoader} instance with the specified matchers.
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/EmbeddedServletContainerInitializedEvent.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/EmbeddedServletContainerInitializedEvent.java
index 0019f8b5d8..cf2b6af5f4 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/EmbeddedServletContainerInitializedEvent.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/EmbeddedServletContainerInitializedEvent.java
@@ -29,7 +29,7 @@ import org.springframework.context.ApplicationEvent;
  */
 public class EmbeddedServletContainerInitializedEvent extends ApplicationEvent {
 
-	private ApplicationContext applicationContext;
+	private final ApplicationContext applicationContext;
 
 	public EmbeddedServletContainerInitializedEvent(
 			ApplicationContext applicationContext, EmbeddedServletContainer source) {
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/ErrorPage.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/ErrorPage.java
index fbe908703b..642a811d30 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/ErrorPage.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/ErrorPage.java
@@ -27,7 +27,7 @@ import org.springframework.util.ObjectUtils;
  */
 public class ErrorPage {
 
-	private String path;
+	private final String path;
 
 	private Class<? extends Throwable> exception = null;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainer.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainer.java
index 755b1a229b..710bb69c92 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainer.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainer.java
@@ -40,7 +40,7 @@ public class JettyEmbeddedServletContainer implements EmbeddedServletContainer {
 	private final Log logger = LogFactory.getLog(JettyEmbeddedServletContainer.class);
 
 	private final Server server;
-	private boolean autoStart;
+	private final boolean autoStart;
 
 	/**
 	 * Create a new {@link JettyEmbeddedServletContainer} instance.
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/ServletContextInitializerConfiguration.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/ServletContextInitializerConfiguration.java
index d18d61b182..5f917d9cd0 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/ServletContextInitializerConfiguration.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/ServletContextInitializerConfiguration.java
@@ -33,9 +33,9 @@ import org.springframework.util.Assert;
  */
 public class ServletContextInitializerConfiguration extends AbstractConfiguration {
 
-	private ContextHandler contextHandler;
+	private final ContextHandler contextHandler;
 
-	private ServletContextInitializer[] initializers;
+	private final ServletContextInitializer[] initializers;
 
 	/**
 	 * Create a new {@link ServletContextInitializerConfiguration}.
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/ServletContextInitializerLifecycleListener.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/ServletContextInitializerLifecycleListener.java
index 0a3e65e93e..4bcc8496e0 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/ServletContextInitializerLifecycleListener.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/ServletContextInitializerLifecycleListener.java
@@ -32,7 +32,7 @@ import org.springframework.util.Assert;
  */
 public class ServletContextInitializerLifecycleListener implements LifecycleListener {
 
-	private ServletContextInitializer[] initializers;
+	private final ServletContextInitializer[] initializers;
 
 	/**
 	 * Create a new {@link ServletContextInitializerLifecycleListener} instance with the
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainer.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainer.java
index 268c08430c..e2decf8547 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainer.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainer.java
@@ -47,7 +47,7 @@ public class TomcatEmbeddedServletContainer implements EmbeddedServletContainer
 
 	private final Tomcat tomcat;
 
-	private boolean autoStart;
+	private final boolean autoStart;
 
 	/**
 	 * Create a new {@link TomcatEmbeddedServletContainer} instance.
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.java b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.java
index 2a68c18809..34552999b2 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.java
@@ -420,11 +420,11 @@ public class TomcatEmbeddedServletContainerFactory extends
 
 	private static class TomcatErrorPage {
 
-		private String location;
-		private String exceptionType;
-		private int errorCode;
+		private final String location;
+		private final String exceptionType;
+		private final int errorCode;
 
-		private Object nativePage;
+		private final Object nativePage;
 
 		public TomcatErrorPage(ErrorPage errorPage) {
 			this.location = errorPage.getPath();
@@ -487,7 +487,7 @@ public class TomcatEmbeddedServletContainerFactory extends
 	 */
 	private static class StoreMergedWebXmlListener implements LifecycleListener {
 
-		private String MERGED_WEB_XML = org.apache.tomcat.util.scan.Constants.MERGED_WEB_XML;
+		private final String MERGED_WEB_XML = org.apache.tomcat.util.scan.Constants.MERGED_WEB_XML;
 
 		@Override
 		public void lifecycleEvent(LifecycleEvent event) {
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializer.java b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializer.java
index 89dfe7942d..98cba8cc10 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializer.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializer.java
@@ -59,7 +59,7 @@ public class ContextIdApplicationContextInitializer implements
 	 */
 	private static final String INDEX_PATTERN = "${vcap.application.instance_index:${spring.application.index:${server.port:${PORT:null}}}}";
 
-	private String name;
+	private final String name;
 
 	private int order = Integer.MAX_VALUE - 10;
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ParentContextApplicationContextInitializer.java b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ParentContextApplicationContextInitializer.java
index 03de0c5190..719de7ce82 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ParentContextApplicationContextInitializer.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ParentContextApplicationContextInitializer.java
@@ -31,7 +31,7 @@ public class ParentContextApplicationContextInitializer implements
 
 	private int order = Integer.MIN_VALUE;
 
-	private ApplicationContext parent;
+	private final ApplicationContext parent;
 
 	public ParentContextApplicationContextInitializer(ApplicationContext parent) {
 		this.parent = parent;
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ServletContextApplicationContextInitializer.java b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ServletContextApplicationContextInitializer.java
index 058dedf8f7..3f175f3a54 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/initializer/ServletContextApplicationContextInitializer.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/initializer/ServletContextApplicationContextInitializer.java
@@ -32,7 +32,7 @@ public class ServletContextApplicationContextInitializer implements
 
 	private int order = Integer.MIN_VALUE;
 
-	private ServletContext servletContext;
+	private final ServletContext servletContext;
 
 	/**
 	 * @param servletContext
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/listener/ConfigFileApplicationListener.java b/spring-boot/src/main/java/org/springframework/boot/context/listener/ConfigFileApplicationListener.java
index 07808c5aa6..0b90e807ac 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/listener/ConfigFileApplicationListener.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/listener/ConfigFileApplicationListener.java
@@ -98,11 +98,11 @@ public class ConfigFileApplicationListener implements
 
 	private int order = Integer.MIN_VALUE + 10;
 
-	private Map<String, PropertySource<?>> cached = new HashMap<String, PropertySource<?>>();
+	private final Map<String, PropertySource<?>> cached = new HashMap<String, PropertySource<?>>();
 
-	private ConversionService conversionService = new DefaultConversionService();
+	private final ConversionService conversionService = new DefaultConversionService();
 
-	private PropertySourceAnnotations propertySourceAnnotations = new PropertySourceAnnotations();
+	private final PropertySourceAnnotations propertySourceAnnotations = new PropertySourceAnnotations();
 
 	private PropertySourceLoaderFactory propertySourceLoaderFactory = new DefaultPropertySourceLoaderFactory();
 
@@ -411,13 +411,13 @@ public class ConfigFileApplicationListener implements
 
 	private static class PropertySourceAnnotations {
 
-		private Collection<String> locations = new LinkedHashSet<String>();
+		private final Collection<String> locations = new LinkedHashSet<String>();
 
-		private Map<String, String> names = new HashMap<String, String>();
+		private final Map<String, String> names = new HashMap<String, String>();
 
-		private Map<String, Class<?>> configs = new HashMap<String, Class<?>>();
+		private final Map<String, Class<?>> configs = new HashMap<String, Class<?>>();
 
-		private Map<String, Boolean> ignores = new HashMap<String, Boolean>();
+		private final Map<String, Boolean> ignores = new HashMap<String, Boolean>();
 
 		public void add(Class<?> source, String[] locations,
 				boolean ignoreResourceNotFound, String name) {
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/listener/VcapApplicationListener.java b/spring-boot/src/main/java/org/springframework/boot/context/listener/VcapApplicationListener.java
index 8d972362c9..ffa3c23801 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/listener/VcapApplicationListener.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/listener/VcapApplicationListener.java
@@ -101,7 +101,7 @@ public class VcapApplicationListener implements
 	// use these ones
 	private int order = Integer.MIN_VALUE + 9;
 
-	private JsonParser parser = JsonParserFactory.getJsonParser();
+	private final JsonParser parser = JsonParserFactory.getJsonParser();
 
 	public void setOrder(int order) {
 		this.order = order;
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java b/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java
index bd749c7843..75c45472af 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java
@@ -78,11 +78,11 @@ public class ConfigurationPropertiesBindingPostProcessor implements BeanPostProc
 
 	private ConversionService conversionService;
 
-	private DefaultConversionService defaultConversionService = new DefaultConversionService();
+	private final DefaultConversionService defaultConversionService = new DefaultConversionService();
 
 	private BeanFactory beanFactory;
 
-	private boolean initialized = false;
+	private final boolean initialized = false;
 
 	private ResourceLoader resourceLoader = new DefaultResourceLoader();
 
diff --git a/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesHolder.java b/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesHolder.java
index eff0f2fbd2..0ac26355a5 100644
--- a/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesHolder.java
+++ b/spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesHolder.java
@@ -24,7 +24,7 @@ package org.springframework.boot.context.properties;
  */
 class ConfigurationPropertiesHolder {
 
-	private Object target;
+	private final Object target;
 
 	public ConfigurationPropertiesHolder(Object target) {
 		this.target = target;
diff --git a/spring-boot/src/test/java/org/springframework/boot/OverrideSourcesTests.java b/spring-boot/src/test/java/org/springframework/boot/OverrideSourcesTests.java
index 2735b87606..05d6e78a52 100644
--- a/spring-boot/src/test/java/org/springframework/boot/OverrideSourcesTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/OverrideSourcesTests.java
@@ -83,7 +83,7 @@ public class OverrideSourcesTests {
 
 	protected static class TestBean {
 
-		private String name;
+		private final String name;
 
 		public TestBean(String name) {
 			this.name = name;
diff --git a/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java b/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java
index 56562aa019..abf8f96a50 100644
--- a/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java
@@ -521,13 +521,13 @@ public class SpringApplicationTests {
 	static class TestCommandLineRunner implements CommandLineRunner,
 			ApplicationContextAware, Ordered {
 
-		private String[] expectedBefore;
+		private final String[] expectedBefore;
 
 		private ApplicationContext applicationContext;
 
 		private String[] args;
 
-		private int order;
+		private final int order;
 
 		public TestCommandLineRunner(int order, String... expectedBefore) {
 			this.expectedBefore = expectedBefore;
diff --git a/spring-boot/src/test/java/org/springframework/boot/StartUpLoggerTests.java b/spring-boot/src/test/java/org/springframework/boot/StartUpLoggerTests.java
index aa98d246e1..80c0a53653 100644
--- a/spring-boot/src/test/java/org/springframework/boot/StartUpLoggerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/StartUpLoggerTests.java
@@ -28,9 +28,9 @@ import static org.junit.Assert.assertTrue;
  */
 public class StartUpLoggerTests {
 
-	private StringBuffer output = new StringBuffer();
+	private final StringBuffer output = new StringBuffer();
 
-	private SimpleLog log = new SimpleLog("test") {
+	private final SimpleLog log = new SimpleLog("test") {
 		@Override
 		protected void write(StringBuffer buffer) {
 			StartUpLoggerTests.this.output.append(buffer).append("\n");
diff --git a/spring-boot/src/test/java/org/springframework/boot/bind/PropertySourcesPropertyValuesTests.java b/spring-boot/src/test/java/org/springframework/boot/bind/PropertySourcesPropertyValuesTests.java
index c8a1273c23..780b15b4cb 100644
--- a/spring-boot/src/test/java/org/springframework/boot/bind/PropertySourcesPropertyValuesTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/bind/PropertySourcesPropertyValuesTests.java
@@ -34,7 +34,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class PropertySourcesPropertyValuesTests {
 
-	private MutablePropertySources propertySources = new MutablePropertySources();
+	private final MutablePropertySources propertySources = new MutablePropertySources();
 
 	@Before
 	public void init() {
diff --git a/spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java b/spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java
index 709601673e..53fa188011 100644
--- a/spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java
@@ -538,7 +538,7 @@ public class RelaxedDataBinderTests {
 	}
 
 	public static class TargetWithReadOnlyNestedList {
-		private List<String> nested = new ArrayList<String>();
+		private final List<String> nested = new ArrayList<String>();
 
 		public List<String> getNested() {
 			return this.nested;
@@ -546,7 +546,7 @@ public class RelaxedDataBinderTests {
 	}
 
 	public static class TargetWithReadOnlyNestedCollection {
-		private Collection<String> nested = new ArrayList<String>();
+		private final Collection<String> nested = new ArrayList<String>();
 
 		public Collection<String> getNested() {
 			return this.nested;
diff --git a/spring-boot/src/test/java/org/springframework/boot/bind/YamlConfigurationFactoryTests.java b/spring-boot/src/test/java/org/springframework/boot/bind/YamlConfigurationFactoryTests.java
index 749a248131..576341b8cd 100644
--- a/spring-boot/src/test/java/org/springframework/boot/bind/YamlConfigurationFactoryTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/bind/YamlConfigurationFactoryTests.java
@@ -41,7 +41,7 @@ public class YamlConfigurationFactoryTests {
 
 	private Validator validator;
 
-	private Map<Class<?>, Map<String, String>> aliases = new HashMap<Class<?>, Map<String, String>>();
+	private final Map<Class<?>, Map<String, String>> aliases = new HashMap<Class<?>, Map<String, String>>();
 
 	private Foo createFoo(final String yaml) throws Exception {
 		YamlConfigurationFactory<Foo> factory = new YamlConfigurationFactory<Foo>(
diff --git a/spring-boot/src/test/java/org/springframework/boot/builder/SpringApplicationBuilderTests.java b/spring-boot/src/test/java/org/springframework/boot/builder/SpringApplicationBuilderTests.java
index fb4a8a3a99..0721591403 100644
--- a/spring-boot/src/test/java/org/springframework/boot/builder/SpringApplicationBuilderTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/builder/SpringApplicationBuilderTests.java
@@ -215,7 +215,7 @@ public class SpringApplicationBuilderTests {
 
 	public static class SpyApplicationContext extends AnnotationConfigApplicationContext {
 
-		private ConfigurableApplicationContext applicationContext = spy(new AnnotationConfigApplicationContext());
+		private final ConfigurableApplicationContext applicationContext = spy(new AnnotationConfigApplicationContext());
 		private ResourceLoader resourceLoader;
 
 		@Override
diff --git a/spring-boot/src/test/java/org/springframework/boot/config/SimpleJsonParserTests.java b/spring-boot/src/test/java/org/springframework/boot/config/SimpleJsonParserTests.java
index 6190e6099c..d7ba93d98a 100644
--- a/spring-boot/src/test/java/org/springframework/boot/config/SimpleJsonParserTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/config/SimpleJsonParserTests.java
@@ -30,7 +30,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class SimpleJsonParserTests {
 
-	private JsonParser parser = getParser();
+	private final JsonParser parser = getParser();
 
 	protected JsonParser getParser() {
 		return new SimpleJsonParser();
diff --git a/spring-boot/src/test/java/org/springframework/boot/config/YamlMapFactoryBeanTests.java b/spring-boot/src/test/java/org/springframework/boot/config/YamlMapFactoryBeanTests.java
index dad98d3228..8bffe4cb07 100644
--- a/spring-boot/src/test/java/org/springframework/boot/config/YamlMapFactoryBeanTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/config/YamlMapFactoryBeanTests.java
@@ -38,7 +38,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class YamlMapFactoryBeanTests {
 
-	private YamlMapFactoryBean factory = new YamlMapFactoryBean();
+	private final YamlMapFactoryBean factory = new YamlMapFactoryBean();
 
 	@Test
 	public void testSetIgnoreResourceNotFound() throws Exception {
diff --git a/spring-boot/src/test/java/org/springframework/boot/config/YamlProcessorTests.java b/spring-boot/src/test/java/org/springframework/boot/config/YamlProcessorTests.java
index e5446be6ca..d593f7f758 100644
--- a/spring-boot/src/test/java/org/springframework/boot/config/YamlProcessorTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/config/YamlProcessorTests.java
@@ -36,7 +36,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class YamlProcessorTests {
 
-	private YamlProcessor processor = new YamlProcessor();
+	private final YamlProcessor processor = new YamlProcessor();
 
 	@Rule
 	public ExpectedException exception = ExpectedException.none();
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/embedded/FilterRegistrationBeanTests.java b/spring-boot/src/test/java/org/springframework/boot/context/embedded/FilterRegistrationBeanTests.java
index 88df4a737b..8484171bb4 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/embedded/FilterRegistrationBeanTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/embedded/FilterRegistrationBeanTests.java
@@ -48,7 +48,7 @@ public class FilterRegistrationBeanTests {
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
 
-	private MockFilter filter = new MockFilter();
+	private final MockFilter filter = new MockFilter();
 
 	@Mock
 	private ServletContext servletContext;
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/embedded/MockEmbeddedServletContainerFactory.java b/spring-boot/src/test/java/org/springframework/boot/context/embedded/MockEmbeddedServletContainerFactory.java
index 7f978e5db6..8e328ab066 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/embedded/MockEmbeddedServletContainerFactory.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/embedded/MockEmbeddedServletContainerFactory.java
@@ -77,13 +77,13 @@ public class MockEmbeddedServletContainerFactory extends
 
 		private ServletContext servletContext;
 
-		private ServletContextInitializer[] initializers;
+		private final ServletContextInitializer[] initializers;
 
-		private List<RegisteredServlet> registeredServlets = new ArrayList<RegisteredServlet>();
+		private final List<RegisteredServlet> registeredServlets = new ArrayList<RegisteredServlet>();
 
-		private List<RegisteredFilter> registeredFilters = new ArrayList<RegisteredFilter>();
+		private final List<RegisteredFilter> registeredFilters = new ArrayList<RegisteredFilter>();
 
-		private int port;
+		private final int port;
 
 		public MockEmbeddedServletContainer(ServletContextInitializer[] initializers,
 				int port) {
@@ -187,9 +187,9 @@ public class MockEmbeddedServletContainerFactory extends
 
 	public static class RegisteredServlet {
 
-		private Servlet servlet;
+		private final Servlet servlet;
 
-		private ServletRegistration.Dynamic registration;
+		private final ServletRegistration.Dynamic registration;
 
 		public RegisteredServlet(Servlet servlet) {
 			this.servlet = servlet;
@@ -207,9 +207,9 @@ public class MockEmbeddedServletContainerFactory extends
 
 	public static class RegisteredFilter {
 
-		private Filter filter;
+		private final Filter filter;
 
-		private FilterRegistration.Dynamic registration;
+		private final FilterRegistration.Dynamic registration;
 
 		public RegisteredFilter(Filter filter) {
 			this.filter = filter;
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletListenerRegistrationBeanTests.java b/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletListenerRegistrationBeanTests.java
index 4371c4c344..181db38994 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletListenerRegistrationBeanTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletListenerRegistrationBeanTests.java
@@ -41,7 +41,7 @@ public class ServletListenerRegistrationBeanTests {
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
 
-	private ServletContextListener listener = Mockito.mock(ServletContextListener.class);
+	private final ServletContextListener listener = Mockito.mock(ServletContextListener.class);
 
 	@Mock
 	private ServletContext servletContext;
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletRegistrationBeanTests.java b/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletRegistrationBeanTests.java
index 02cebe97ae..9dd5887c93 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletRegistrationBeanTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/embedded/ServletRegistrationBeanTests.java
@@ -50,7 +50,7 @@ public class ServletRegistrationBeanTests {
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
 
-	private MockServlet servlet = new MockServlet();
+	private final MockServlet servlet = new MockServlet();
 
 	@Mock
 	private ServletContext servletContext;
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializerTests.java
index 74a50c0b07..fd6aa2beeb 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/initializer/ContextIdApplicationContextInitializerTests.java
@@ -30,7 +30,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class ContextIdApplicationContextInitializerTests {
 
-	private ContextIdApplicationContextInitializer initializer = new ContextIdApplicationContextInitializer();
+	private final ContextIdApplicationContextInitializer initializer = new ContextIdApplicationContextInitializer();
 
 	@Test
 	public void testDefaults() {
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/initializer/EnvironmentDelegateApplicationContextInitializerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/initializer/EnvironmentDelegateApplicationContextInitializerTests.java
index 6e180244f0..d25a763165 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/initializer/EnvironmentDelegateApplicationContextInitializerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/initializer/EnvironmentDelegateApplicationContextInitializerTests.java
@@ -41,7 +41,7 @@ public class EnvironmentDelegateApplicationContextInitializerTests {
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
 
-	private EnvironmentDelegateApplicationContextInitializer initializer = new EnvironmentDelegateApplicationContextInitializer();
+	private final EnvironmentDelegateApplicationContextInitializer initializer = new EnvironmentDelegateApplicationContextInitializer();
 
 	@Test
 	public void orderedInitialize() throws Exception {
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/listener/ConfigFileApplicationListenerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/listener/ConfigFileApplicationListenerTests.java
index 759d0549a6..4c6361830b 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/listener/ConfigFileApplicationListenerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/listener/ConfigFileApplicationListenerTests.java
@@ -57,12 +57,12 @@ import static org.junit.Assert.assertThat;
  */
 public class ConfigFileApplicationListenerTests {
 
-	private StandardEnvironment environment = new StandardEnvironment();
+	private final StandardEnvironment environment = new StandardEnvironment();
 
-	private SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
+	private final SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
 			new SpringApplication(), this.environment, new String[0]);
 
-	private ConfigFileApplicationListener initializer = new ConfigFileApplicationListener();
+	private final ConfigFileApplicationListener initializer = new ConfigFileApplicationListener();
 
 	@Rule
 	public ExpectedException expected = ExpectedException.none();
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/listener/EnvironmentDelegateApplicationListenerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/listener/EnvironmentDelegateApplicationListenerTests.java
index b4175a6b03..89f84aa2cb 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/listener/EnvironmentDelegateApplicationListenerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/listener/EnvironmentDelegateApplicationListenerTests.java
@@ -38,9 +38,9 @@ public class EnvironmentDelegateApplicationListenerTests {
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
 
-	private EnvironmentDelegateApplicationListener listener = new EnvironmentDelegateApplicationListener();
+	private final EnvironmentDelegateApplicationListener listener = new EnvironmentDelegateApplicationListener();
 
-	private StaticApplicationContext context = new StaticApplicationContext();
+	private final StaticApplicationContext context = new StaticApplicationContext();
 
 	@After
 	public void close() {
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/listener/FileEncodingApplicationListenerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/listener/FileEncodingApplicationListenerTests.java
index 269c1a44f6..fb19d95c8d 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/listener/FileEncodingApplicationListenerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/listener/FileEncodingApplicationListenerTests.java
@@ -31,9 +31,9 @@ import org.springframework.core.env.StandardEnvironment;
  */
 public class FileEncodingApplicationListenerTests {
 
-	private FileEncodingApplicationListener initializer = new FileEncodingApplicationListener();
-	private ConfigurableEnvironment environment = new StandardEnvironment();
-	private SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
+	private final FileEncodingApplicationListener initializer = new FileEncodingApplicationListener();
+	private final ConfigurableEnvironment environment = new StandardEnvironment();
+	private final SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
 			new SpringApplication(), this.environment, new String[0]);
 
 	@Test(expected = IllegalStateException.class)
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/listener/LoggingApplicationListenerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/listener/LoggingApplicationListenerTests.java
index fd8001de44..8ceaccdf9a 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/listener/LoggingApplicationListenerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/listener/LoggingApplicationListenerTests.java
@@ -57,13 +57,13 @@ public class LoggingApplicationListenerTests {
 	@Rule
 	public OutputCapture outputCapture = new OutputCapture();
 
-	private LoggingApplicationListener initializer = new LoggingApplicationListener();
+	private final LoggingApplicationListener initializer = new LoggingApplicationListener();
 
-	private Log logger = new SLF4JLogFactory().getInstance(getClass());
+	private final Log logger = new SLF4JLogFactory().getInstance(getClass());
 
-	private SpringApplication springApplication = new SpringApplication();
+	private final SpringApplication springApplication = new SpringApplication();
 
-	private GenericApplicationContext context = new GenericApplicationContext();
+	private final GenericApplicationContext context = new GenericApplicationContext();
 
 	@Before
 	public void init() throws SecurityException, IOException {
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/listener/VcapApplicationListenerTests.java b/spring-boot/src/test/java/org/springframework/boot/context/listener/VcapApplicationListenerTests.java
index c090a4d8a8..2e9498df3a 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/listener/VcapApplicationListenerTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/listener/VcapApplicationListenerTests.java
@@ -32,9 +32,9 @@ import static org.junit.Assert.assertEquals;
  */
 public class VcapApplicationListenerTests {
 
-	private VcapApplicationListener initializer = new VcapApplicationListener();
-	private ConfigurableApplicationContext context = new AnnotationConfigApplicationContext();
-	private SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
+	private final VcapApplicationListener initializer = new VcapApplicationListener();
+	private final ConfigurableApplicationContext context = new AnnotationConfigApplicationContext();
+	private final SpringApplicationEnvironmentAvailableEvent event = new SpringApplicationEnvironmentAvailableEvent(
 			new SpringApplication(), this.context.getEnvironment(), new String[0]);
 
 	@Test
diff --git a/spring-boot/src/test/java/org/springframework/boot/context/properties/EnableConfigurationPropertiesTests.java b/spring-boot/src/test/java/org/springframework/boot/context/properties/EnableConfigurationPropertiesTests.java
index e4ada88e9e..fcac2d5644 100644
--- a/spring-boot/src/test/java/org/springframework/boot/context/properties/EnableConfigurationPropertiesTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/context/properties/EnableConfigurationPropertiesTests.java
@@ -49,7 +49,7 @@ import static org.junit.Assert.assertNotNull;
  */
 public class EnableConfigurationPropertiesTests {
 
-	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
 	@Rule
 	public ExpectedException expected = ExpectedException.none();
@@ -504,7 +504,7 @@ public class EnableConfigurationPropertiesTests {
 
 		private String name;
 
-		private Nested nested = new Nested();
+		private final Nested nested = new Nested();
 
 		public void setName(String name) {
 			this.name = name;
@@ -547,7 +547,7 @@ public class EnableConfigurationPropertiesTests {
 
 		private int[] array;
 
-		private List<Integer> list = new ArrayList<Integer>();
+		private final List<Integer> list = new ArrayList<Integer>();
 
 		// No getter - you should be able to bind to a write-only bean
 
diff --git a/spring-boot/src/test/java/org/springframework/boot/logging/java/JavaLoggerSystemTests.java b/spring-boot/src/test/java/org/springframework/boot/logging/java/JavaLoggerSystemTests.java
index d8994ea88f..6865749bac 100644
--- a/spring-boot/src/test/java/org/springframework/boot/logging/java/JavaLoggerSystemTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/logging/java/JavaLoggerSystemTests.java
@@ -39,7 +39,7 @@ import static org.junit.Assert.assertTrue;
  */
 public class JavaLoggerSystemTests {
 
-	private JavaLoggingSystem loggingSystem = new JavaLoggingSystem(getClass()
+	private final JavaLoggingSystem loggingSystem = new JavaLoggingSystem(getClass()
 			.getClassLoader());
 
 	@Rule
diff --git a/spring-boot/src/test/java/org/springframework/boot/logging/log4j/Log4JLoggingSystemTests.java b/spring-boot/src/test/java/org/springframework/boot/logging/log4j/Log4JLoggingSystemTests.java
index 80ad3809f0..f7261cf003 100644
--- a/spring-boot/src/test/java/org/springframework/boot/logging/log4j/Log4JLoggingSystemTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/logging/log4j/Log4JLoggingSystemTests.java
@@ -39,7 +39,7 @@ public class Log4JLoggingSystemTests {
 	@Rule
 	public OutputCapture output = new OutputCapture();
 
-	private Log4JLoggingSystem loggingSystem = new Log4JLoggingSystem(getClass()
+	private final Log4JLoggingSystem loggingSystem = new Log4JLoggingSystem(getClass()
 			.getClassLoader());
 
 	private Log4JLogger logger;
diff --git a/spring-boot/src/test/java/org/springframework/boot/logging/logback/ColorConverterTests.java b/spring-boot/src/test/java/org/springframework/boot/logging/logback/ColorConverterTests.java
index e00bde025c..a9aff2ce7f 100644
--- a/spring-boot/src/test/java/org/springframework/boot/logging/logback/ColorConverterTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/logging/logback/ColorConverterTests.java
@@ -39,7 +39,7 @@ public class ColorConverterTests {
 
 	private ColorConverter converter;
 	private LoggingEvent event;
-	private String in = "in";
+	private final String in = "in";
 
 	@BeforeClass
 	public static void setupAnsi() {
diff --git a/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java b/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java
index 216fd20f7f..8430c1001d 100644
--- a/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java
@@ -40,7 +40,7 @@ public class LogbackLoggingSystemTests {
 	@Rule
 	public OutputCapture output = new OutputCapture();
 
-	private LogbackLoggingSystem loggingSystem = new LogbackLoggingSystem(getClass()
+	private final LogbackLoggingSystem loggingSystem = new LogbackLoggingSystem(getClass()
 			.getClassLoader());
 
 	private Log logger;
diff --git a/spring-boot/src/test/java/org/springframework/boot/logging/logback/WhitespaceThrowableProxyConverterTests.java b/spring-boot/src/test/java/org/springframework/boot/logging/logback/WhitespaceThrowableProxyConverterTests.java
index 04b146d44d..0d91293273 100644
--- a/spring-boot/src/test/java/org/springframework/boot/logging/logback/WhitespaceThrowableProxyConverterTests.java
+++ b/spring-boot/src/test/java/org/springframework/boot/logging/logback/WhitespaceThrowableProxyConverterTests.java
@@ -36,9 +36,9 @@ public class WhitespaceThrowableProxyConverterTests {
 
 	private static final String LINE_SEPARATOR = System.getProperty("line.separator");
 
-	private WhitespaceThrowableProxyConverter converter = new WhitespaceThrowableProxyConverter();
+	private final WhitespaceThrowableProxyConverter converter = new WhitespaceThrowableProxyConverter();
 
-	private LoggingEvent event = new LoggingEvent();
+	private final LoggingEvent event = new LoggingEvent();
 
 	@Test
 	public void noStackTrace() throws Exception {