Reduce PropertySource access when binding

Update `PropertiesConfigurationFactory` so that when possible fewer
calls are made to the underlying `PropertySource`. The
`PropertySourcesPropertyValues` class now accepts a matcher which is
used to limit the properties that should be adapted. The factory will
create a matcher based on the standard relaxed binding rules.

Fixes gh-3402
See gh-3515

spring-boot/src/main/java/org/springframework/boot/bind/DefaultPropertyNamePatternsMatcher.java

@@ -21,22 +21,34 @@ import java.util.HashSet;
 import java.util.Set;
 
 /**
- * Default {@link PropertyNamePatternsMatcher} that matches when a property name exactly
- * matches one of the given names, or starts with one of the given names followed by '.'
- * or '_'. This implementation is optimized for frequent calls.
+ * {@link PropertyNamePatternsMatcher} that matches when a property name exactly matches
+ * one of the given names, or starts with one of the given names followed by a delimiter.
+ * This implementation is optimized for frequent calls.
  *
  * @author Phillip Webb
  * @since 1.2.0
  */
 class DefaultPropertyNamePatternsMatcher implements PropertyNamePatternsMatcher {
 
+	private final char[] delimiters;
+
+	private final boolean ignoreCase;
+
 	private final String[] names;
 
-	public DefaultPropertyNamePatternsMatcher(String... names) {
-		this(new HashSet<String>(Arrays.asList(names)));
+	protected DefaultPropertyNamePatternsMatcher(char[] delimiters, String... names) {
+		this(delimiters, false, names);
 	}
 
-	public DefaultPropertyNamePatternsMatcher(Set<String> names) {
+	protected DefaultPropertyNamePatternsMatcher(char[] delimiters, boolean ignoreCase,
+			String... names) {
+		this(delimiters, ignoreCase, new HashSet<String>(Arrays.asList(names)));
+	}
+
+	public DefaultPropertyNamePatternsMatcher(char[] delimiters, boolean ignoreCase,
+			Set<String> names) {
+		this.delimiters = delimiters;
+		this.ignoreCase = ignoreCase;
 		this.names = names.toArray(new String[names.size()]);
 	}
 
@@ -55,18 +67,19 @@ class DefaultPropertyNamePatternsMatcher implements PropertyNamePatternsMatcher
 			return false;
 		}
 		for (int charIndex = 0; charIndex < propertyNameChars.length; charIndex++) {
-			noneMatched = true;
 			for (int nameIndex = 0; nameIndex < this.names.length; nameIndex++) {
 				if (match[nameIndex]) {
+					match[nameIndex] = false;
 					if (charIndex < this.names[nameIndex].length()) {
-						if (this.names[nameIndex].charAt(charIndex) == propertyNameChars[charIndex]) {
+						if (isCharMatch(this.names[nameIndex].charAt(charIndex),
+								propertyNameChars[charIndex])) {
 							match[nameIndex] = true;
 							noneMatched = false;
 						}
 					}
 					else {
 						char charAfter = propertyNameChars[this.names[nameIndex].length()];
-						if (charAfter == '.' || charAfter == '_') {
+						if (isDelimeter(charAfter)) {
 							match[nameIndex] = true;
 							noneMatched = false;
 						}
@@ -85,4 +98,20 @@ class DefaultPropertyNamePatternsMatcher implements PropertyNamePatternsMatcher
 		return false;
 	}
 
+	private boolean isCharMatch(char c1, char c2) {
+		if (this.ignoreCase) {
+			return Character.toLowerCase(c1) == Character.toLowerCase(c2);
+		}
+		return c1 == c2;
+	}
+
+	private boolean isDelimeter(char c) {
+		for (char delimiter : this.delimiters) {
+			if (c == delimiter) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 }

spring-boot/src/main/java/org/springframework/boot/bind/PatternPropertyNamePatternsMatcher.java

@@ -27,11 +27,11 @@ import org.springframework.util.PatternMatchUtils;
  * @author Phillip Webb
  * @since 1.2.0
  */
-class SimplePropertyNamePatternsMatcher implements PropertyNamePatternsMatcher {
+class PatternPropertyNamePatternsMatcher implements PropertyNamePatternsMatcher {
 
 	private final String[] patterns;
 
-	public SimplePropertyNamePatternsMatcher(Collection<String> patterns) {
+	public PatternPropertyNamePatternsMatcher(Collection<String> patterns) {
 		this.patterns = (patterns == null ? new String[] {} : patterns
 				.toArray(new String[patterns.size()]));
 	}

spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java

@@ -17,8 +17,9 @@
 package org.springframework.boot.bind;
 
 import java.beans.PropertyDescriptor;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.Locale;
+import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
 
@@ -34,6 +35,7 @@ import org.springframework.context.MessageSourceAware;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.env.PropertySources;
 import org.springframework.util.Assert;
+import org.springframework.util.StringUtils;
 import org.springframework.validation.BindException;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.DataBinder;
@@ -51,6 +53,10 @@ import org.springframework.validation.Validator;
 public class PropertiesConfigurationFactory<T> implements FactoryBean<T>,
 		MessageSourceAware, InitializingBean {
 
+	private static final char[] EXACT_DELIMETERS = { '_', '.', '[' };
+
+	private static final char[] TARGET_NAME_DELIMETERS = { '_', '.' };
+
 	private final Log logger = LogFactory.getLog(getClass());
 
 	private boolean ignoreUnknownFields = true;
@@ -257,16 +263,28 @@ public class PropertiesConfigurationFactory<T> implements FactoryBean<T>,
 	}
 
 	private Set<String> getNames() {
-		Set<String> names = new HashSet<String>();
+		Set<String> names = new LinkedHashSet<String>();
 		if (this.target != null) {
+			Iterable<String> prefixes = (StringUtils.hasLength(this.targetName) ? new RelaxedNames(
+					this.targetName) : null);
 			PropertyDescriptor[] descriptors = BeanUtils
 					.getPropertyDescriptors(this.target.getClass());
-			String prefix = (this.targetName != null ? this.targetName + "." : "");
 			for (PropertyDescriptor descriptor : descriptors) {
 				String name = descriptor.getName();
 				if (!name.equals("class")) {
-					for (String relaxedName : new RelaxedNames(prefix + name)) {
-						names.add(relaxedName);
+					RelaxedNames relaxedNames = RelaxedNames.forCamelCase(name);
+					if (prefixes == null) {
+						for (String relaxedName : relaxedNames) {
+							names.add(relaxedName);
+						}
+					}
+					else {
+						for (String prefix : prefixes) {
+							for (String relaxedName : relaxedNames) {
+								names.add(prefix + "." + relaxedName);
+								names.add(prefix + "_" + relaxedName);
+							}
+						}
 					}
 				}
 			}
@@ -278,8 +296,33 @@ public class PropertiesConfigurationFactory<T> implements FactoryBean<T>,
 		if (this.properties != null) {
 			return new MutablePropertyValues(this.properties);
 		}
-		return new PropertySourcesPropertyValues(this.propertySources,
-				new DefaultPropertyNamePatternsMatcher(names), names);
+		return getPropertySourcesPropertyValues(names);
+	}
+
+	private PropertyValues getPropertySourcesPropertyValues(Set<String> names) {
+		PropertyNamePatternsMatcher includes = getPropertyNamePatternsMatcher(names);
+		return new PropertySourcesPropertyValues(this.propertySources, names, includes);
+	}
+
+	private PropertyNamePatternsMatcher getPropertyNamePatternsMatcher(Set<String> names) {
+		if (this.ignoreUnknownFields && !isMapTarget()) {
+			// Since unknown fields are ignored we can filter them out early to save
+			// unnecessary calls to the PropertySource.
+			return new DefaultPropertyNamePatternsMatcher(EXACT_DELIMETERS, true, names);
+		}
+		if (this.targetName != null) {
+			// We can filter properties to those starting with the target name, but
+			// we can't do a complete filter since we need to trigger the
+			// unknown fields check
+			return new DefaultPropertyNamePatternsMatcher(TARGET_NAME_DELIMETERS,
+					this.targetName);
+		}
+		// Not ideal, we basically can't filter anything
+		return PropertyNamePatternsMatcher.ALL;
+	}
+
+	private boolean isMapTarget() {
+		return this.target != null && Map.class.isAssignableFrom(this.target.getClass());
 	}
 
 	private void validate(RelaxedDataBinder dataBinder) throws BindException {

spring-boot/src/main/java/org/springframework/boot/bind/PropertyNamePatternsMatcher.java

@@ -24,6 +24,15 @@ package org.springframework.boot.bind;
  */
 interface PropertyNamePatternsMatcher {
 
+	PropertyNamePatternsMatcher ALL = new PropertyNamePatternsMatcher() {
+
+		@Override
+		public boolean matches(String propertyName) {
+			return true;
+		}
+
+	};
+
 	PropertyNamePatternsMatcher NONE = new PropertyNamePatternsMatcher() {
 
 		@Override

spring-boot/src/main/java/org/springframework/boot/bind/PropertySourcesPropertyValues.java

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.bind;
 
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashMap;
@@ -30,7 +29,7 @@ import org.springframework.core.env.EnumerablePropertySource;
 import org.springframework.core.env.PropertySource;
 import org.springframework.core.env.PropertySources;
 import org.springframework.core.env.PropertySourcesPropertyResolver;
-import org.springframework.core.env.StandardEnvironment;
+import org.springframework.util.Assert;
 import org.springframework.validation.DataBinder;
 
 /**
@@ -46,17 +45,16 @@ public class PropertySourcesPropertyValues implements PropertyValues {
 
 	private final PropertySources propertySources;
 
-	private static final Collection<String> PATTERN_MATCHED_PROPERTY_SOURCES = Arrays
-			.asList(StandardEnvironment.SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME,
-					StandardEnvironment.SYSTEM_PROPERTIES_PROPERTY_SOURCE_NAME);
+	private final Collection<String> propertyNames;
+
+	private final PropertyNamePatternsMatcher includes;
 
 	/**
 	 * Create a new PropertyValues from the given PropertySources
 	 * @param propertySources a PropertySources instance
 	 */
 	public PropertySourcesPropertyValues(PropertySources propertySources) {
-		this(propertySources, (PropertyNamePatternsMatcher) null,
-				(Collection<String>) null);
+		this(propertySources, (Collection<String>) null, PropertyNamePatternsMatcher.ALL);
 	}
 
 	/**
@@ -64,52 +62,55 @@ public class PropertySourcesPropertyValues implements PropertyValues {
 	 * @param propertySources a PropertySources instance
 	 * @param includePatterns property name patterns to include from system properties and
 	 * environment variables
-	 * @param names exact property names to include
+	 * @param propertyNames the property names to used in lieu of an
+	 * {@link EnumerablePropertySource}.
 	 */
 	public PropertySourcesPropertyValues(PropertySources propertySources,
-			Collection<String> includePatterns, Collection<String> names) {
-		this(propertySources, new SimplePropertyNamePatternsMatcher(includePatterns),
-				names);
+			Collection<String> includePatterns, Collection<String> propertyNames) {
+		this(propertySources, propertyNames, new PatternPropertyNamePatternsMatcher(
+				includePatterns));
 	}
 
 	/**
 	 * Create a new PropertyValues from the given PropertySources
 	 * @param propertySources a PropertySources instance
-	 * @param includes property name patterns to include from system properties and
-	 * environment variables
-	 * @param names exact property names to include
+	 * @param propertyNames the property names to used in lieu of an
+	 * {@link EnumerablePropertySource}.
+	 * @param includes the property name patterns to include
 	 */
 	PropertySourcesPropertyValues(PropertySources propertySources,
-			PropertyNamePatternsMatcher includes, Collection<String> names) {
+			Collection<String> propertyNames, PropertyNamePatternsMatcher includes) {
+		Assert.notNull(propertySources, "PropertySources must not be null");
+		Assert.notNull(includes, "Includes must not be null");
 		this.propertySources = propertySources;
-		if (includes == null) {
-			includes = PropertyNamePatternsMatcher.NONE;
-		}
-		if (names == null) {
-			names = Collections.emptySet();
-		}
+		this.propertyNames = (propertyNames == null ? Collections.<String> emptySet()
+				: propertyNames);
+		this.includes = includes;
 		PropertySourcesPropertyResolver resolver = new PropertySourcesPropertyResolver(
 				propertySources);
 		for (PropertySource<?> source : propertySources) {
-			processPropertySource(source, resolver, includes, names);
+			processPropertySource(source, resolver);
 		}
 	}
 
 	private void processPropertySource(PropertySource<?> source,
-			PropertySourcesPropertyResolver resolver,
-			PropertyNamePatternsMatcher includes, Collection<String> exacts) {
+			PropertySourcesPropertyResolver resolver) {
 		if (source instanceof CompositePropertySource) {
-			processCompositePropertySource((CompositePropertySource) source, resolver,
-					includes, exacts);
+			processCompositePropertySource((CompositePropertySource) source, resolver);
 		}
 		else if (source instanceof EnumerablePropertySource) {
 			processEnumerablePropertySource((EnumerablePropertySource<?>) source,
-					resolver, includes);
+					resolver, this.includes);
 		}
 		else {
-			// We can only do exact matches for non-enumerable property names, but
-			// that's better than nothing...
-			processDefaultPropertySource(source, resolver, includes, exacts);
+			processNonEnumerablePropertySource(source, resolver);
+		}
+	}
+
+	private void processCompositePropertySource(CompositePropertySource source,
+			PropertySourcesPropertyResolver resolver) {
+		for (PropertySource<?> nested : source.getPropertySources()) {
+			processPropertySource(nested, resolver);
 		}
 	}
 
@@ -117,14 +118,9 @@ public class PropertySourcesPropertyValues implements PropertyValues {
 			PropertySourcesPropertyResolver resolver, PropertyNamePatternsMatcher includes) {
 		if (source.getPropertyNames().length > 0) {
 			for (String propertyName : source.getPropertyNames()) {
-				if (PropertySourcesPropertyValues.PATTERN_MATCHED_PROPERTY_SOURCES
-						.contains(source.getName()) && !includes.matches(propertyName)) {
-					continue;
-				}
-				Object value = getEnumerableProperty(source, resolver, propertyName);
-				if (!this.propertyValues.containsKey(propertyName)) {
-					this.propertyValues.put(propertyName, new PropertyValue(propertyName,
-							value));
+				if (includes.matches(propertyName)) {
+					Object value = getEnumerableProperty(source, resolver, propertyName);
+					putIfAbsent(propertyName, value);
 				}
 			}
 		}
@@ -141,18 +137,11 @@ public class PropertySourcesPropertyValues implements PropertyValues {
 		}
 	}
 
-	private void processCompositePropertySource(CompositePropertySource source,
-			PropertySourcesPropertyResolver resolver,
-			PropertyNamePatternsMatcher includes, Collection<String> exacts) {
-		for (PropertySource<?> nested : source.getPropertySources()) {
-			processPropertySource(nested, resolver, includes, exacts);
-		}
-	}
-
-	private void processDefaultPropertySource(PropertySource<?> source,
-			PropertySourcesPropertyResolver resolver,
-			PropertyNamePatternsMatcher includes, Collection<String> exacts) {
-		for (String propertyName : exacts) {
+	private void processNonEnumerablePropertySource(PropertySource<?> source,
+			PropertySourcesPropertyResolver resolver) {
+		// We can only do exact matches for non-enumerable property names, but
+		// that's better than nothing...
+		for (String propertyName : this.propertyNames) {
 			if (!source.containsProperty(propertyName)) {
 				continue;
 			}
@@ -166,11 +155,13 @@ public class PropertySourcesPropertyValues implements PropertyValues {
 			if (value == null) {
 				value = source.getProperty(propertyName.toUpperCase());
 			}
-			if (value != null && !this.propertyValues.containsKey(propertyName)) {
-				this.propertyValues.put(propertyName, new PropertyValue(propertyName,
-						value));
-				continue;
-			}
+			putIfAbsent(propertyName, value);
+		}
+	}
+
+	private void putIfAbsent(String propertyName, Object value) {
+		if (value != null && !this.propertyValues.containsKey(propertyName)) {
+			this.propertyValues.put(propertyName, new PropertyValue(propertyName, value));
 		}
 	}
 

spring-boot/src/main/java/org/springframework/boot/bind/RelaxedNames.java

@@ -188,4 +188,13 @@ public final class RelaxedNames implements Iterable<String> {
 		}
 	}
 
+	/**
+	 * Return a {@link RelaxedNames} for the given source camelCase source name
+	 * @param name the source name in camelCase
+	 * @return the relaxed names
+	 */
+	public static RelaxedNames forCamelCase(String name) {
+		return new RelaxedNames(Manipulation.CAMELCASE_TO_HYPHEN.apply(name));
+	}
+
 }

spring-boot/src/test/java/org/springframework/boot/bind/DefaultPropertyNamePatternsMatcherTests.java

@@ -28,42 +28,53 @@ import static org.junit.Assert.assertTrue;
  */
 public class DefaultPropertyNamePatternsMatcherTests {
 
+	private static final char[] DELIMITERS = { '.', '_' };
+
 	@Test
 	public void namesShorter() {
-		assertFalse(new DefaultPropertyNamePatternsMatcher("aaaa", "bbbb")
+		assertFalse(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaaa", "bbbb")
 				.matches("zzzzz"));
 
 	}
 
 	@Test
 	public void namesExactMatch() {
-		assertTrue(new DefaultPropertyNamePatternsMatcher("aaaa", "bbbb", "cccc")
-				.matches("bbbb"));
+		assertTrue(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaaa", "bbbb",
+				"cccc").matches("bbbb"));
 	}
 
 	@Test
 	public void namesLonger() {
-		assertFalse(new DefaultPropertyNamePatternsMatcher("aaaaa", "bbbbb", "ccccc")
-				.matches("bbbb"));
+		assertFalse(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaaaa", "bbbbb",
+				"ccccc").matches("bbbb"));
 	}
 
 	@Test
 	public void nameWithDot() throws Exception {
-		assertTrue(new DefaultPropertyNamePatternsMatcher("aaaa", "bbbb", "cccc")
-				.matches("bbbb.anything"));
+		assertTrue(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaaa", "bbbb",
+				"cccc").matches("bbbb.anything"));
 	}
 
 	@Test
 	public void nameWithUnderscore() throws Exception {
-		assertTrue(new DefaultPropertyNamePatternsMatcher("aaaa", "bbbb", "cccc")
-				.matches("bbbb_anything"));
+		assertTrue(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaaa", "bbbb",
+				"cccc").matches("bbbb_anything"));
 	}
 
 	@Test
 	public void namesMatchWithDifferentLengths() throws Exception {
-		assertTrue(new DefaultPropertyNamePatternsMatcher("aaa", "bbbb", "ccccc")
-				.matches("bbbb"));
+		assertTrue(new DefaultPropertyNamePatternsMatcher(DELIMITERS, "aaa", "bbbb",
+				"ccccc").matches("bbbb"));
+	}
 
+	@Test
+	public void withSquareBrackets() throws Exception {
+		char[] delimeters = "._[".toCharArray();
+		PropertyNamePatternsMatcher matcher = new DefaultPropertyNamePatternsMatcher(
+				delimeters, "aaa", "bbbb", "ccccc");
+		assertTrue(matcher.matches("bbbb"));
+		assertTrue(matcher.matches("bbbb[4]"));
+		assertFalse(matcher.matches("bbb[4]"));
 	}
 
 }

spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java

@@ -102,6 +102,20 @@ public class RelaxedDataBinderTests {
 		assertEquals("bar", target.getFoo());
 	}
 
+	@Test
+	public void testBindToCamelCaseFromEnvironmentStyleWithPrefix() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "TEST_FOO_BAZ: bar", "test");
+		assertEquals("bar", target.getFooBaz());
+	}
+
+	@Test
+	public void testBindToCamelCaseFromEnvironmentStyle() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "test.FOO_BAZ: bar", "test");
+		assertEquals("bar", target.getFooBaz());
+	}
+
 	@Test
 	public void testBindFromEnvironmentStyleWithNestedPrefix() throws Exception {
 		VanillaTarget target = new VanillaTarget();