Remove DataSerializable serialization logic from GemFireSession and GemFireSessionAttributes classes.

Move Delta serialization logic to new DeltaCapableGemFireSession and DeltaCapableGemFireSessionAttributes subclasses.

Fix up all test class compilation issues and failures.

Resolves Issue #2.

spring-session-data-geode/src/integration-test/java/org/springframework/session/data/gemfire/ClientServerGemFireOperationsSessionRepositoryIntegrationTests.java

@@ -17,6 +17,7 @@
 package org.springframework.session.data.gemfire;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.data.gemfire.util.ArrayUtils.asArray;
 
 import java.io.File;
 import java.io.IOException;
@@ -25,9 +26,7 @@ import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.time.Duration;
 import java.time.Instant;
-import java.util.Collections;
 import java.util.Date;
-import java.util.Properties;
 import java.util.concurrent.TimeUnit;
 
 import org.junit.After;
@@ -37,9 +36,7 @@ import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
-import org.apache.geode.cache.Cache;
 import org.apache.geode.cache.DataPolicy;
-import org.apache.geode.cache.GemFireCache;
 import org.apache.geode.cache.Region;
 import org.apache.geode.cache.RegionAttributes;
 import org.apache.geode.cache.client.ClientCache;
@@ -51,10 +48,10 @@ import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
-import org.springframework.data.gemfire.CacheFactoryBean;
-import org.springframework.data.gemfire.client.ClientCacheFactoryBean;
-import org.springframework.data.gemfire.client.PoolFactoryBean;
-import org.springframework.data.gemfire.server.CacheServerFactoryBean;
+import org.springframework.data.gemfire.config.annotation.CacheServerApplication;
+import org.springframework.data.gemfire.config.annotation.CacheServerConfigurer;
+import org.springframework.data.gemfire.config.annotation.ClientCacheApplication;
+import org.springframework.data.gemfire.config.annotation.ClientCacheConfigurer;
 import org.springframework.data.gemfire.support.ConnectionEndpoint;
 import org.springframework.session.Session;
 import org.springframework.session.data.gemfire.config.annotation.web.http.EnableGemFireHttpSession;
@@ -71,31 +68,36 @@ import org.springframework.util.FileSystemUtils;
 import org.springframework.util.SocketUtils;
 
 /**
- * Integration tests to test the functionality of GemFire-backed Spring Sessions using
- * the GemFire client-server topology.
+ * Integration tests testing the functionality of Apache Geode / Pivotal GemFire backed Spring Sessions
+ * using the GemFire client-server topology.
  *
  * @author John Blum
  * @since 1.1.0
  * @see org.junit.Test
  * @see org.junit.runner.RunWith
- * @see org.springframework.context.ConfigurableApplicationContext
- * @see org.springframework.session.Session
- * @see org.springframework.session.data.gemfire.AbstractGemFireIntegrationTests
- * @see org.springframework.session.data.gemfire.config.annotation.web.http.EnableGemFireHttpSession
- * @see org.springframework.session.data.gemfire.config.annotation.web.http.GemFireHttpSessionConfiguration
- * @see org.springframework.test.annotation.DirtiesContext
- * @see org.springframework.test.context.ContextConfiguration
- * @see org.springframework.test.context.junit4.SpringRunner
- * @see org.springframework.test.context.web.WebAppConfiguration
  * @see org.apache.geode.cache.Cache
  * @see org.apache.geode.cache.Region
  * @see org.apache.geode.cache.client.ClientCache
  * @see org.apache.geode.cache.client.Pool
  * @see org.apache.geode.cache.server.CacheServer
+ * @see org.springframework.context.ConfigurableApplicationContext
+ * @see org.springframework.data.gemfire.config.annotation.CacheServerApplication
+ * @see org.springframework.data.gemfire.config.annotation.ClientCacheApplication
+ * @see org.springframework.session.Session
+ * @see org.springframework.session.data.gemfire.AbstractGemFireIntegrationTests
+ * @see org.springframework.session.data.gemfire.config.annotation.web.http.EnableGemFireHttpSession
+ * @see org.springframework.session.data.gemfire.config.annotation.web.http.GemFireHttpSessionConfiguration
+ * @see org.springframework.session.events.SessionCreatedEvent
+ * @see org.springframework.session.events.SessionDeletedEvent
+ * @see org.springframework.session.events.SessionExpiredEvent
+ * @see org.springframework.test.annotation.DirtiesContext
+ * @see org.springframework.test.context.ContextConfiguration
+ * @see org.springframework.test.context.junit4.SpringRunner
+ * @see org.springframework.test.context.web.WebAppConfiguration
  */
 @RunWith(SpringRunner.class)
 @ContextConfiguration(classes =
-	ClientServerGemFireOperationsSessionRepositoryIntegrationTests.SpringSessionDataGemFireClientConfiguration.class)
+	ClientServerGemFireOperationsSessionRepositoryIntegrationTests.TestGemFireClientConfiguration.class)
 @DirtiesContext
 @WebAppConfiguration
 public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
@@ -109,9 +111,10 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 
 	private static Process gemfireServer;
 
-	private static final String SPRING_SESSION_GEMFIRE_REGION_NAME = "TestClientServerSessions";
+	private static final String TEST_SESSION_REGION_NAME = "TestClientServerSessions";
 
 	@Autowired
+	@SuppressWarnings("all")
 	private SessionEventListener sessionEventListener;
 
 	@BeforeClass
@@ -122,7 +125,7 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 		int port = SocketUtils.findAvailableTcpPort();
 
 		System.err.printf("Starting a GemFire Server running on host [%1$s] listening on port [%2$d]%n",
-			SpringSessionDataGemFireServerConfiguration.SERVER_HOSTNAME, port);
+			TestGemFireServerConfiguration.SERVER_HOSTNAME, port);
 
 		System.setProperty("spring.session.data.gemfire.port", String.valueOf(port));
 
@@ -131,10 +134,10 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 
 		processWorkingDirectory = createDirectory(processWorkingDirectoryPathname);
 
-		gemfireServer = run(SpringSessionDataGemFireServerConfiguration.class, processWorkingDirectory,
+		gemfireServer = run(TestGemFireServerConfiguration.class, processWorkingDirectory,
 			String.format("-Dspring.session.data.gemfire.port=%1$d", port));
 
-		assertThat(waitForCacheServerToStart(SpringSessionDataGemFireServerConfiguration.SERVER_HOSTNAME, port))
+		assertThat(waitForCacheServerToStart(TestGemFireServerConfiguration.SERVER_HOSTNAME, port))
 			.isTrue();
 
 		System.err.printf("GemFire Server [startup time = %1$d ms]%n", System.currentTimeMillis() - t0);
@@ -164,7 +167,7 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 		assertThat(GemFireUtils.isClient(gemfireCache)).isTrue();
 
 		Region<Object, Session> springSessionGemFireRegion =
-			gemfireCache.getRegion(SPRING_SESSION_GEMFIRE_REGION_NAME);
+			gemfireCache.getRegion(TEST_SESSION_REGION_NAME);
 
 		assertThat(springSessionGemFireRegion).isNotNull();
 
@@ -257,53 +260,25 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 		assertThat(deletedSession).isNull();
 	}
 
-	@EnableGemFireHttpSession(regionName = SPRING_SESSION_GEMFIRE_REGION_NAME,
+	@ClientCacheApplication(logLevel = "warning", pingInterval = 5000, readTimeout = 2500, retryAttempts = 1,
+		subscriptionEnabled = true)
+	@EnableGemFireHttpSession(regionName = TEST_SESSION_REGION_NAME, poolName = "DEFAULT",
 		clientRegionShortcut = ClientRegionShortcut.CACHING_PROXY,
 			maxInactiveIntervalInSeconds = MAX_INACTIVE_INTERVAL_IN_SECONDS)
 	@SuppressWarnings("unused")
-	static class SpringSessionDataGemFireClientConfiguration {
+	static class TestGemFireClientConfiguration {
 
 		@Bean
 		static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
 			return new PropertySourcesPlaceholderConfigurer();
 		}
 
-		Properties gemfireProperties() {
-
-			Properties gemfireProperties = new Properties();
-
-			gemfireProperties.setProperty("log-level", GEMFIRE_LOG_LEVEL);
-
-			return gemfireProperties;
-		}
-
 		@Bean
-		ClientCacheFactoryBean gemfireCache() {
-
-			ClientCacheFactoryBean clientCacheFactory = new ClientCacheFactoryBean();
-
-			clientCacheFactory.setClose(true);
-			clientCacheFactory.setProperties(gemfireProperties());
-
-			return clientCacheFactory;
-		}
-
-		@Bean
-		PoolFactoryBean gemfirePool(
+		ClientCacheConfigurer clientCacheDefaultPoolPortConfigurer(
 				@Value("${spring.session.data.gemfire.port:" + DEFAULT_GEMFIRE_SERVER_PORT + "}") int port) {
 
-			PoolFactoryBean poolFactory = new PoolFactoryBean();
-
-			poolFactory.setKeepAlive(false);
-			poolFactory.setPingInterval(TimeUnit.SECONDS.toMillis(5));
-			poolFactory.setReadTimeout(2000); // 2 seconds
-			poolFactory.setRetryAttempts(1);
-			poolFactory.setSubscriptionEnabled(true);
-
-			poolFactory.setServers(Collections.singletonList(new ConnectionEndpoint(
-				SpringSessionDataGemFireServerConfiguration.SERVER_HOSTNAME, port)));
-
-			return poolFactory;
+			return (beanName, clientCacheFactoryBean) ->
+				clientCacheFactoryBean.setServers(asArray(new ConnectionEndpoint("localhost", port)));
 		}
 
 		@Bean
@@ -316,7 +291,7 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 		public static void main(String[] args) {
 
 			ConfigurableApplicationContext applicationContext = new AnnotationConfigApplicationContext(
-					SpringSessionDataGemFireClientConfiguration.class);
+					TestGemFireClientConfiguration.class);
 
 			applicationContext.registerShutdownHook();
 
@@ -329,10 +304,12 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 		}
 	}
 
-	@EnableGemFireHttpSession(regionName = SPRING_SESSION_GEMFIRE_REGION_NAME,
+	@CacheServerApplication(name = "ClientServerGemFireOperationsSessionRepositoryIntegrationTests",
+		logLevel = "warning")
+	@EnableGemFireHttpSession(regionName = TEST_SESSION_REGION_NAME,
 		maxInactiveIntervalInSeconds = MAX_INACTIVE_INTERVAL_IN_SECONDS)
 	@SuppressWarnings("unused")
-	static class SpringSessionDataGemFireServerConfiguration {
+	static class TestGemFireServerConfiguration {
 
 		static final String SERVER_HOSTNAME = "localhost";
 
@@ -341,53 +318,20 @@ public class ClientServerGemFireOperationsSessionRepositoryIntegrationTests
 			return new PropertySourcesPlaceholderConfigurer();
 		}
 
-		Properties gemfireProperties() {
-
-			Properties gemfireProperties = new Properties();
-
-			gemfireProperties.setProperty("name", name());
-			gemfireProperties.setProperty("mcast-port", "0");
-			gemfireProperties.setProperty("log-level", GEMFIRE_LOG_LEVEL);
-
-			return gemfireProperties;
-		}
-
-		String name() {
-			return ClientServerGemFireOperationsSessionRepositoryIntegrationTests.class.getName();
-		}
-
 		@Bean
-		CacheFactoryBean gemfireCache() {
-
-			CacheFactoryBean gemfireCache = new CacheFactoryBean();
-
-			gemfireCache.setClose(true);
-			gemfireCache.setProperties(gemfireProperties());
-
-			return gemfireCache;
-		}
-
-		@Bean
-		CacheServerFactoryBean gemfireCacheServer(GemFireCache gemfireCache,
+		CacheServerConfigurer cacheServerPortConfigurer(
 				@Value("${spring.session.data.gemfire.port:" + DEFAULT_GEMFIRE_SERVER_PORT + "}") int port) {
 
-			CacheServerFactoryBean cacheServerFactory = new CacheServerFactoryBean();
-
-			cacheServerFactory.setCache((Cache) gemfireCache);
-			cacheServerFactory.setAutoStartup(true);
-			cacheServerFactory.setBindAddress(SERVER_HOSTNAME);
-			cacheServerFactory.setPort(port);
-
-			return cacheServerFactory;
+			return (beanName, cacheServerFactoryBean) -> cacheServerFactoryBean.setPort(port);
 		}
 
 		@SuppressWarnings("resource")
 		public static void main(String[] args) throws IOException {
 
-			AnnotationConfigApplicationContext context =
-				new AnnotationConfigApplicationContext(SpringSessionDataGemFireServerConfiguration.class);
+			AnnotationConfigApplicationContext applicationContext =
+				new AnnotationConfigApplicationContext(TestGemFireServerConfiguration.class);
 
-			context.registerShutdownHook();
+			applicationContext.registerShutdownHook();
 
 			writeProcessControlFile(WORKING_DIRECTORY);
 		}

spring-session-data-geode/src/integration-test/java/org/springframework/session/data/gemfire/GemFireOperationsSessionRepositoryIntegrationTests.java

@@ -48,29 +48,33 @@ import org.springframework.session.Session;
 import org.springframework.session.data.gemfire.config.annotation.web.http.EnableGemFireHttpSession;
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
 /**
- * Integration test to test the {@code findByPrincipalName} query method
- * on {@link GemFireOperationsSessionRepository}.
+ * Integration test to test the {@code findByPrincipalName} query method on {@link GemFireOperationsSessionRepository}.
  *
  * @author John Blum
  * @since 1.1.0
  * @see org.junit.Test
  * @see org.junit.runner.RunWith
+ * @see org.apache.geode.cache.Region
+ * @see org.apache.geode.cache.query.QueryService
+ * @see org.apache.geode.pdx.PdxSerializable
+ * @see org.springframework.data.gemfire.config.annotation.PeerCacheApplication
+ * @see org.springframework.security.core.context.SecurityContext
+ * @see org.springframework.session.Session
  * @see org.springframework.session.data.gemfire.AbstractGemFireIntegrationTests
  * @see org.springframework.session.data.gemfire.GemFireOperationsSessionRepository
+ * @see org.springframework.session.data.gemfire.config.annotation.web.http.EnableGemFireHttpSession
  * @see org.springframework.test.annotation.DirtiesContext
  * @see org.springframework.test.context.ContextConfiguration
- * @see org.springframework.test.context.junit4.SpringJUnit4ClassRunner
+ * @see org.springframework.test.context.junit4.SpringRunner
  * @see org.springframework.test.context.web.WebAppConfiguration
- * @see org.apache.geode.cache.Cache
- * @see org.apache.geode.cache.Region
  */
-@RunWith(SpringJUnit4ClassRunner.class)
+@RunWith(SpringRunner.class)
 @ContextConfiguration
 @DirtiesContext
 @WebAppConfiguration
@@ -328,8 +332,8 @@ public class GemFireOperationsSessionRepositoryIntegrationTests extends Abstract
 
 		((AbstractGemFireOperationsSessionRepository.GemFireSession) expectedSession).setPrincipalName("jblum");
 
-		List<String> expectedAttributeNames = Arrays.asList("booleanAttribute", "numericAttribute", "stringAttribute",
-			"personAttribute");
+		List<String> expectedAttributeNames =
+			Arrays.asList("booleanAttribute", "numericAttribute", "stringAttribute", "personAttribute");
 
 		Person jonDoe = new Person("Jon", "Doe");
 
@@ -406,13 +410,13 @@ public class GemFireOperationsSessionRepositoryIntegrationTests extends Abstract
 			pdxWriter.writeString("lastName", getLastName());
 		}
 
-		public void fromData(final PdxReader pdxReader) {
+		public void fromData(PdxReader pdxReader) {
 			this.firstName = pdxReader.readString("firstName");
 			this.lastName = pdxReader.readString("lastName");
 		}
 
 		@SuppressWarnings("all")
-		public int compareTo(final Person person) {
+		public int compareTo(Person person) {
 
 			int compareValue = getLastName().compareTo(person.getLastName());
 
@@ -420,7 +424,7 @@ public class GemFireOperationsSessionRepositoryIntegrationTests extends Abstract
 		}
 
 		@Override
-		public boolean equals(final Object obj) {
+		public boolean equals(Object obj) {
 
 			if (this == obj) {
 				return true;

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/AbstractGemFireOperationsSessionRepository.java

@@ -16,6 +16,8 @@
 
 package org.springframework.session.data.gemfire;
 
+import static org.springframework.data.gemfire.util.RuntimeExceptionFactory.newIllegalArgumentException;
+
 import java.io.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
@@ -32,6 +34,7 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentSkipListSet;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.geode.DataSerializable;
 import org.apache.geode.DataSerializer;
@@ -93,7 +96,7 @@ import org.apache.commons.logging.LogFactory;
 public abstract class AbstractGemFireOperationsSessionRepository extends CacheListenerAdapter<Object, Session>
 		implements ApplicationEventPublisherAware, FindByIndexNameSessionRepository<Session>, InitializingBean {
 
-	private boolean usingDataSerialization = false;
+	private static final AtomicBoolean usingDataSerialization = new AtomicBoolean(false);
 
 	private ApplicationEventPublisher applicationEventPublisher = new ApplicationEventPublisher() {
 
@@ -246,7 +249,7 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 	 * @param useDataSerialization boolean indicating whether the DataSerialization framework has been configured.
 	 */
 	public void setUseDataSerialization(boolean useDataSerialization) {
-		this.usingDataSerialization = useDataSerialization;
+		usingDataSerialization.set(useDataSerialization);
 	}
 
 	/**
@@ -254,8 +257,8 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 	 *
 	 * @return a boolean indicating whether the DataSerialization framework has been configured.
 	 */
-	protected boolean isUsingDataSerialization() {
-		return this.usingDataSerialization;
+	protected static boolean isUsingDataSerialization() {
+		return usingDataSerialization.get();
 	}
 
 	/**
@@ -292,9 +295,6 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		this.fullyQualifiedRegionName = region.getFullPath();
 
 		region.getAttributesMutator().addCacheListener(this);
-
-		Instantiator.register(GemFireSessionInstantiator.create());
-		Instantiator.register(GemFireSessionAttributesInstantiator.create());
 	}
 
 	/* (non-Javadoc) */
@@ -524,22 +524,57 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		return session;
 	}
 
+	@SuppressWarnings("unused")
+	public static class DeltaCapableGemFireSession extends GemFireSession<DeltaCapableGemFireSessionAttributes>
+			implements Delta {
+
+		public DeltaCapableGemFireSession() { }
+
+		public DeltaCapableGemFireSession(String id) {
+			super(id);
+		}
+
+		public DeltaCapableGemFireSession(Session session) {
+			super(session);
+		}
+
+		@Override
+		protected DeltaCapableGemFireSessionAttributes newSessionAttributes(Object lock) {
+			return new DeltaCapableGemFireSessionAttributes();
+		}
+
+		/* (non-Javadoc) */
+		public synchronized void toDelta(DataOutput out) throws IOException {
+
+			out.writeUTF(getId());
+			out.writeLong(getLastAccessedTime().toEpochMilli());
+			out.writeLong(getMaxInactiveInterval().getSeconds());
+			getAttributes().toDelta(out);
+			clearDelta();
+		}
+
+		/* (non-Javadoc) */
+		public synchronized void fromDelta(DataInput in) throws IOException {
+
+			setId(in.readUTF());
+			setLastAccessedTime(Instant.ofEpochMilli(in.readLong()));
+			setMaxInactiveInterval(Duration.ofSeconds(in.readLong()));
+			getAttributes().fromDelta(in);
+			clearDelta();
+		}
+	}
+
 	/**
-	 * {@link GemFireSession} is a GemFire model for a Spring {@link Session} that stores and manages {@link Session}
-	 * state in GemFire. This class implements GemFire's {@link DataSerializable} interface to better handle
-	 * replication of {@link Session} state across the GemFire cluster.
+	 * {@link GemFireSession} is a Abstract Data Type (ADT) for a Spring {@link Session} that stores and manages
+	 * {@link Session} state in Apache Geode or Pivotal GemFire.
 	 *
 	 * @see java.lang.Comparable
-	 * @see org.apache.geode.DataSerializable
-	 * @see org.apache.geode.Delta
 	 * @see org.springframework.session.Session
 	 */
 	@SuppressWarnings("serial")
-	public static class GemFireSession implements Comparable<Session>, DataSerializable, Delta, Session {
+	public static class GemFireSession<T extends GemFireSessionAttributes> implements Comparable<Session>, Session {
 
-		protected static final boolean DEFAULT_ALLOW_JAVA_SERIALIZATION = true;
-
-		private static final Duration DEFAULT_MAX_INACTIVE_INTERVAL = Duration.ZERO;
+		protected static final Duration DEFAULT_MAX_INACTIVE_INTERVAL = Duration.ZERO;
 
 		protected static final String SPRING_SECURITY_CONTEXT = "SPRING_SECURITY_CONTEXT";
 
@@ -547,8 +582,6 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		private Duration maxInactiveInterval = DEFAULT_MAX_INACTIVE_INTERVAL;
 
-		private transient final GemFireSessionAttributes sessionAttributes = new GemFireSessionAttributes(this);
-
 		private Instant creationTime;
 		private Instant lastAccessedTime;
 
@@ -556,6 +589,8 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		private String id;
 
+		private transient final T sessionAttributes = newSessionAttributes(this);
+
 		/* (non-Javadoc) */
 		protected GemFireSession() {
 			this(generateId());
@@ -582,13 +617,19 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		/* (non-Javadoc) */
 		public static GemFireSession copy(Session session) {
-			return new GemFireSession(session);
+			return (isUsingDataSerialization() ? new DeltaCapableGemFireSession(session) : new GemFireSession(session));
+		}
+
+		/* (non-Javadoc) */
+		public static GemFireSession create() {
+			return create(DEFAULT_MAX_INACTIVE_INTERVAL);
 		}
 
 		/* (non-Javadoc) */
 		public static GemFireSession create(Duration maxInactiveInterval) {
 
-			GemFireSession session = new GemFireSession();
+			GemFireSession session =
+				(isUsingDataSerialization() ? new DeltaCapableGemFireSession() : new GemFireSession());
 
 			session.setMaxInactiveInterval(maxInactiveInterval);
 
@@ -596,8 +637,9 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		}
 
 		/* (non-Javadoc) */
-		public static GemFireSession from(Session session) {
-			return (session instanceof GemFireSession ? (GemFireSession) session : copy(session));
+		@SuppressWarnings("unchecked")
+		public static <T extends GemFireSession> T from(Session session) {
+			return (T) (session instanceof GemFireSession ? (GemFireSession) session : copy(session));
 		}
 
 		/**
@@ -612,32 +654,53 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		/* (non-Javadoc) */
 		private static String validateId(String id) {
-
 			return Optional.ofNullable(id).filter(StringUtils::hasText)
-				.orElseThrow(() -> new IllegalArgumentException("ID is required"));
+				.orElseThrow(() -> newIllegalArgumentException("ID is required"));
+		}
+
+		@SuppressWarnings("unchecked")
+		protected T newSessionAttributes(Object lock) {
+			return (T) new GemFireSessionAttributes(lock);
 		}
 
 		/* (non-Javadoc) */
-		protected boolean allowJavaSerialization() {
-			return DEFAULT_ALLOW_JAVA_SERIALIZATION;
-		}
-
 		@Override
 		public synchronized String changeSessionId() {
 
 			this.id = generateId();
+			triggerDelta();
 
 			return getId();
 		}
 
 		/* (non-Javadoc) */
-		public synchronized String getId() {
-			return this.id;
+		public synchronized void clearDelta() {
+			this.delta = false;
 		}
 
 		/* (non-Javadoc) */
-		public synchronized Instant getCreationTime() {
-			return this.creationTime;
+		public synchronized boolean hasDelta() {
+			return (this.delta || this.sessionAttributes.hasDelta());
+		}
+
+		/* (non-Javadoc) */
+		@SuppressWarnings("unused")
+		protected void triggerDelta() {
+			triggerDelta(true);
+		}
+
+		/* (non-Javadoc) */
+		protected synchronized void triggerDelta(boolean condition) {
+			this.delta |= condition;
+		}
+
+		synchronized void setId(String id) {
+			this.id = validateId(id);
+		}
+
+		/* (non-Javadoc) */
+		public synchronized String getId() {
+			return this.id;
 		}
 
 		/* (non-Javadoc) */
@@ -661,10 +724,15 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		}
 
 		/* (non-Javadoc) */
-		public GemFireSessionAttributes getAttributes() {
+		public T getAttributes() {
 			return this.sessionAttributes;
 		}
 
+		/* (non-Javadoc) */
+		public synchronized Instant getCreationTime() {
+			return this.creationTime;
+		}
+
 		/* (non-Javadoc) */
 		public synchronized boolean isExpired() {
 
@@ -688,7 +756,7 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		/* (non-Javadoc) */
 		public synchronized void setLastAccessedTime(Instant lastAccessedTime) {
-			this.delta |= !ObjectUtils.nullSafeEquals(this.lastAccessedTime, lastAccessedTime);
+			triggerDelta(!ObjectUtils.nullSafeEquals(this.lastAccessedTime, lastAccessedTime));
 			this.lastAccessedTime = lastAccessedTime;
 		}
 
@@ -699,7 +767,7 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 
 		/* (non-Javadoc) */
 		public synchronized void setMaxInactiveInterval(Duration maxInactiveIntervalInSeconds) {
-			this.delta |= !ObjectUtils.nullSafeEquals(this.maxInactiveInterval, maxInactiveIntervalInSeconds);
+			triggerDelta(!ObjectUtils.nullSafeEquals(this.maxInactiveInterval, maxInactiveIntervalInSeconds));
 			this.maxInactiveInterval = maxInactiveIntervalInSeconds;
 		}
 
@@ -733,79 +801,6 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 			return principalName;
 		}
 
-		/* (non-Javadoc) */
-		public synchronized void toData(DataOutput out) throws IOException {
-
-			out.writeUTF(getId());
-			out.writeLong(getCreationTime().toEpochMilli());
-			out.writeLong(getLastAccessedTime().toEpochMilli());
-			out.writeLong(getMaxInactiveInterval().getSeconds());
-
-			String principalName = getPrincipalName();
-
-			int length = (StringUtils.hasText(principalName) ? principalName.length() : 0);
-
-			out.writeInt(length);
-
-			if (length > 0) {
-				out.writeUTF(principalName);
-			}
-
-			writeObject(this.sessionAttributes, out);
-
-			this.delta = false;
-		}
-
-		/* (non-Javadoc) */
-		void writeObject(Object obj, DataOutput out) throws IOException {
-			DataSerializer.writeObject(obj, out, allowJavaSerialization());
-		}
-
-		/* (non-Javadoc) */
-		public synchronized void fromData(DataInput in) throws ClassNotFoundException, IOException {
-
-			this.id = in.readUTF();
-			this.creationTime = Instant.ofEpochMilli(in.readLong());
-			setLastAccessedTime(Instant.ofEpochMilli(in.readLong()));
-			setMaxInactiveInterval(Duration.ofSeconds(in.readLong()));
-
-			int principalNameLength = in.readInt();
-
-			if (principalNameLength > 0) {
-				setPrincipalName(in.readUTF());
-			}
-
-			this.sessionAttributes.from(this.<GemFireSessionAttributes>readObject(in));
-
-			this.delta = false;
-		}
-
-		/* (non-Javadoc) */
-		<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-			return DataSerializer.readObject(in);
-		}
-
-		/* (non-Javadoc) */
-		public synchronized boolean hasDelta() {
-			return (this.delta || this.sessionAttributes.hasDelta());
-		}
-
-		/* (non-Javadoc) */
-		public synchronized void toDelta(DataOutput out) throws IOException {
-			out.writeLong(getLastAccessedTime().toEpochMilli());
-			out.writeLong(getMaxInactiveInterval().getSeconds());
-			getAttributes().toDelta(out);
-			this.delta = false;
-		}
-
-		/* (non-Javadoc) */
-		public synchronized void fromDelta(DataInput in) throws IOException {
-			setLastAccessedTime(Instant.ofEpochMilli(in.readLong()));
-			setMaxInactiveInterval(Duration.ofSeconds(in.readLong()));
-			getAttributes().fromDelta(in);
-			this.delta = false;
-		}
-
 		/* (non-Javadoc) */
 		@SuppressWarnings("all")
 		public int compareTo(Session session) {
@@ -851,24 +846,120 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		}
 	}
 
-	/**
-	 * GemFireSessionInstantiator is a GemFire {@link Instantiator} use to instantiate instances
-	 * of the {@link GemFireSession} object used in GemFire's data serialization framework when
-	 * persisting Session state in GemFire.
-	 */
-	public static class GemFireSessionInstantiator extends Instantiator {
+	@SuppressWarnings("unused")
+	public static class DeltaCapableGemFireSessionAttributes extends GemFireSessionAttributes implements Delta {
 
-		public static GemFireSessionInstantiator create() {
-			return new GemFireSessionInstantiator(GemFireSession.class, 800813552);
+		private transient final Map<String, Object> sessionAttributeDeltas = new HashMap<>();
+
+		public DeltaCapableGemFireSessionAttributes() {
 		}
 
-		public GemFireSessionInstantiator(Class<? extends DataSerializable> type, int id) {
-			super(type, id);
+		public DeltaCapableGemFireSessionAttributes(Object lock) {
+			super(lock);
 		}
 
+		/* (non-Javadoc) */
+		public Object setAttribute(String attributeName, Object attributeValue) {
+
+			synchronized (getLock()) {
+
+				if (attributeValue != null) {
+
+					Object previousAttributeValue = super.setAttribute(attributeName, attributeValue);
+
+					if (!attributeValue.equals(previousAttributeValue)) {
+						this.sessionAttributeDeltas.put(attributeName, attributeValue);
+					}
+
+					return previousAttributeValue;
+				}
+				else {
+					return removeAttribute(attributeName);
+				}
+			}
+		}
+
+		/* (non-Javadoc) */
 		@Override
-		public DataSerializable newInstance() {
-			return new GemFireSession();
+		public Object removeAttribute(String attributeName) {
+
+			synchronized (getLock()) {
+
+				return Optional.ofNullable(super.removeAttribute(attributeName))
+					.map(previousAttributeValue -> {
+						this.sessionAttributeDeltas.put(attributeName, null);
+						return previousAttributeValue;
+					})
+					.orElse(null);
+			}
+		}
+
+		/* (non-Javadoc) */
+		public void toDelta(DataOutput out) throws IOException {
+
+			synchronized (getLock()) {
+
+				out.writeInt(this.sessionAttributeDeltas.size());
+
+				for (Map.Entry<String, Object> entry : this.sessionAttributeDeltas.entrySet()) {
+					out.writeUTF(entry.getKey());
+					writeObject(entry.getValue(), out);
+				}
+
+				clearDelta();
+			}
+		}
+
+		/* (non-Javadoc) */
+		protected void writeObject(Object value, DataOutput out) throws IOException {
+			DataSerializer.writeObject(value, out);
+		}
+
+		/* (non-Javadoc) */
+		@Override
+		public boolean hasDelta() {
+
+			synchronized (getLock()) {
+				return !this.sessionAttributeDeltas.isEmpty();
+			}
+		}
+
+		/* (non-Javadoc) */
+		public void fromDelta(DataInput in) throws InvalidDeltaException, IOException {
+
+			synchronized (getLock()) {
+				try {
+					int count = in.readInt();
+
+					Map<String, Object> deltas = new HashMap<>(count);
+
+					while (count-- > 0) {
+						deltas.put(in.readUTF(), readObject(in));
+					}
+
+					deltas.forEach((key, value) -> {
+						setAttribute(key, value);
+						this.sessionAttributeDeltas.remove(key);
+					});
+				}
+				catch (ClassNotFoundException cause) {
+					throw new InvalidDeltaException("Class type in data not found", cause);
+				}
+			}
+		}
+
+		/* (non-Javadoc) */
+		protected <T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
+			return DataSerializer.readObject(in);
+		}
+
+		/* (non-Javadoc) */
+		@Override
+		public void clearDelta() {
+
+			synchronized (getLock()) {
+				this.sessionAttributeDeltas.clear();
+			}
 		}
 	}
 
@@ -885,13 +976,9 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 	 * @see org.apache.geode.Delta
 	 */
 	@SuppressWarnings("serial")
-	public static class GemFireSessionAttributes extends AbstractMap<String, Object>
-			implements DataSerializable, Delta {
-
-		protected static final boolean DEFAULT_ALLOW_JAVA_SERIALIZATION = true;
+	public static class GemFireSessionAttributes extends AbstractMap<String, Object> {
 
 		private transient final Map<String, Object> sessionAttributes = new HashMap<>();
-		private transient final Map<String, Object> sessionAttributeDeltas = new HashMap<>();
 
 		private transient final Object lock;
 
@@ -916,52 +1003,40 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 		}
 
 		/* (non-Javadoc) */
-		public void setAttribute(String attributeName, Object attributeValue) {
+		protected Object getLock() {
+			return this.lock;
+		}
 
-			synchronized (this.lock) {
-				if (attributeValue != null) {
-					if (!attributeValue.equals(this.sessionAttributes.put(attributeName, attributeValue))) {
-						this.sessionAttributeDeltas.put(attributeName, attributeValue);
-					}
-				}
-				else {
-					removeAttribute(attributeName);
-				}
+		/* (non-Javadoc) */
+		public Object setAttribute(String attributeName, Object attributeValue) {
+			synchronized (getLock()) {
+				return (attributeValue != null ? this.sessionAttributes.put(attributeName, attributeValue)
+					: removeAttribute(attributeName));
 			}
 		}
 
 		/* (non-Javadoc) */
-		public void removeAttribute(String attributeName) {
-
-			synchronized (this.lock) {
-				if (this.sessionAttributes.remove(attributeName) != null) {
-					this.sessionAttributeDeltas.put(attributeName, null);
-				}
+		public Object removeAttribute(String attributeName) {
+			synchronized (getLock()) {
+				return this.sessionAttributes.remove(attributeName);
 			}
 		}
 
 		/* (non-Javadoc) */
 		@SuppressWarnings("unchecked")
 		public <T> T getAttribute(String attributeName) {
-
-			synchronized (this.lock) {
+			synchronized (getLock()) {
 				return (T) this.sessionAttributes.get(attributeName);
 			}
 		}
 
 		/* (non-Javadoc) */
 		public Set<String> getAttributeNames() {
-
-			synchronized (this.lock) {
+			synchronized (getLock()) {
 				return Collections.unmodifiableSet(new HashSet<>(this.sessionAttributes.keySet()));
 			}
 		}
 
-		/* (non-Javadoc) */
-		protected boolean allowJavaSerialization() {
-			return DEFAULT_ALLOW_JAVA_SERIALIZATION;
-		}
-
 		/* (non-Javadoc); NOTE: entrySet implementation is not Thread-safe. */
 		@Override
 		@SuppressWarnings("all")
@@ -982,109 +1057,39 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 			};
 		}
 
+		/* (non-Javadoc) */
+		public void clearDelta() {
+		}
+
 		/* (non-Javadoc) */
 		public void from(Session session) {
 
-			synchronized (this.lock) {
+			synchronized (getLock()) {
 				session.getAttributeNames().forEach(attributeName ->
 					setAttribute(attributeName, session.getAttribute(attributeName)));
 			}
 		}
 
+		/* (non-Javadoc) */
+		public void from(Map<String, Object> map) {
+
+			synchronized (getLock()) {
+				map.forEach(this::setAttribute);
+			}
+		}
+
 		/* (non-Javadoc) */
 		public void from(GemFireSessionAttributes sessionAttributes) {
 
-			synchronized (this.lock) {
+			synchronized (getLock()) {
 				sessionAttributes.getAttributeNames().forEach(attributeName ->
 					setAttribute(attributeName, sessionAttributes.getAttribute(attributeName)));
 			}
 		}
 
-		/* (non-Javadoc) */
-		public void toData(DataOutput out) throws IOException {
-
-			synchronized (this.lock) {
-
-				Set<String> attributeNames = getAttributeNames();
-
-				out.writeInt(attributeNames.size());
-
-				for (String attributeName : attributeNames) {
-					out.writeUTF(attributeName);
-					writeObject(getAttribute(attributeName), out);
-				}
-			}
-		}
-
-		/* (non-Javadoc) */
-		void writeObject(Object obj, DataOutput out) throws IOException {
-			DataSerializer.writeObject(obj, out, allowJavaSerialization());
-		}
-
-		/* (non-Javadoc) */
-		public void fromData(DataInput in) throws IOException, ClassNotFoundException {
-
-			synchronized (this.lock) {
-
-				for (int count = in.readInt(); count > 0; count--) {
-					setAttribute(in.readUTF(), readObject(in));
-				}
-
-				this.sessionAttributeDeltas.clear();
-			}
-		}
-
-		/* (non-Javadoc) */
-		<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-			return DataSerializer.readObject(in);
-		}
-
 		/* (non-Javadoc) */
 		public boolean hasDelta() {
-
-			synchronized (this.lock) {
-				return !this.sessionAttributeDeltas.isEmpty();
-			}
-		}
-
-		/* (non-Javadoc) */
-		public void toDelta(DataOutput out) throws IOException {
-
-			synchronized (this.lock) {
-
-				out.writeInt(this.sessionAttributeDeltas.size());
-
-				for (Map.Entry<String, Object> entry : this.sessionAttributeDeltas.entrySet()) {
-					out.writeUTF(entry.getKey());
-					writeObject(entry.getValue(), out);
-				}
-
-				this.sessionAttributeDeltas.clear();
-			}
-		}
-
-		/* (non-Javadoc) */
-		public void fromDelta(DataInput in) throws InvalidDeltaException, IOException {
-
-			synchronized (this.lock) {
-				try {
-					int count = in.readInt();
-
-					Map<String, Object> deltas = new HashMap<>(count);
-
-					while (count-- > 0) {
-						deltas.put(in.readUTF(), readObject(in));
-					}
-
-					deltas.forEach((key, value) -> {
-						setAttribute(key, value);
-						this.sessionAttributeDeltas.remove(key);
-					});
-				}
-				catch (ClassNotFoundException e) {
-					throw new InvalidDeltaException("class type in data not found", e);
-				}
-			}
+			return false;
 		}
 
 		@Override
@@ -1092,25 +1097,4 @@ public abstract class AbstractGemFireOperationsSessionRepository extends CacheLi
 			return this.sessionAttributes.toString();
 		}
 	}
-
-	/**
-	 * GemFireSessionAttributesInstantiator is a GemFire {@link Instantiator} use to instantiate instances
-	 * of the {@link GemFireSessionAttributes} object used in GemFire's data serialization framework when
-	 * persisting Session attributes state in GemFire.
-	 */
-	public static class GemFireSessionAttributesInstantiator extends Instantiator {
-
-		public static GemFireSessionAttributesInstantiator create() {
-			return new GemFireSessionAttributesInstantiator(GemFireSessionAttributes.class, 800828008);
-		}
-
-		public GemFireSessionAttributesInstantiator(Class<? extends DataSerializable> type, int id) {
-			super(type, id);
-		}
-
-		@Override
-		public DataSerializable newInstance() {
-			return new GemFireSessionAttributes();
-		}
-	}
 }

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/config/annotation/web/http/GemFireHttpSessionConfiguration.java

@@ -21,6 +21,8 @@ import static org.springframework.data.gemfire.util.RuntimeExceptionFactory.newI
 import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
+import javax.annotation.PostConstruct;
+
 import org.apache.geode.DataSerializer;
 import org.apache.geode.cache.Cache;
 import org.apache.geode.cache.ExpirationAction;
@@ -43,7 +45,6 @@ import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Condition;
 import org.springframework.context.annotation.ConditionContext;
-import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.DependsOn;
 import org.springframework.context.annotation.Import;
@@ -408,6 +409,14 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 			.orElse(DEFAULT_SESSION_SERIALIZER_BEAN_NAME);
 	}
 
+	/**
+	 * Determine whether the configured serialization strategy is using Apache Geode / Pivotal GemFire's
+	 * DataSerialization framework.
+	 *
+	 * @return a boolean value indicating whether the configured serialization strategy is using Apache Geode
+	 * / Pivotal GemFire's DataSerialization framework.
+	 * @see #getSessionSerializerBeanName()
+	 */
 	protected boolean isUsingDataSerialization() {
 		return SESSION_DATA_SERIALIZER_BEAN_NAME.equals(getSessionSerializerBeanName());
 	}
@@ -444,13 +453,20 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 
 		setSessionSerializerBeanName(
 			enableGemFireHttpSessionAttributes.getString("sessionSerializerBeanName"));
+	}
+
+	@PostConstruct
+	public void init() {
+
+		System.err.printf("SETTING SYSTEM PROPERTY (%s) TO (%s) %n", SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME,
+			getSessionSerializerBeanName());
 
 		System.setProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME, getSessionSerializerBeanName());
-
 		getBeanFactory().registerAlias(getSessionSerializerBeanName(), SESSION_SERIALIZER_REGISTERED_ALIAS);
 	}
 
 	@Bean
+	@DependsOn({ SESSION_DATA_SERIALIZER_BEAN_NAME, SESSION_PDX_SERIALIZER_BEAN_NAME })
 	public ClientCacheConfigurer sessionClientCacheConfigurer(
 			@Qualifier(SESSION_SERIALIZER_REGISTERED_ALIAS) SessionSerializer sessionSerializer) {
 
@@ -458,6 +474,7 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 	}
 
 	@Bean
+	@DependsOn({ SESSION_DATA_SERIALIZER_BEAN_NAME, SESSION_PDX_SERIALIZER_BEAN_NAME })
 	public PeerCacheConfigurer sessionPeerCacheConfigurer(
 			@Qualifier(SESSION_SERIALIZER_REGISTERED_ALIAS) SessionSerializer sessionSerializer) {
 
@@ -618,13 +635,13 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 	}
 
 	@Bean(SESSION_DATA_SERIALIZER_BEAN_NAME)
-	@Conditional(DataSerializableSessionSerializerCondition.class)
+	//@Conditional(DataSerializableSessionSerializerCondition.class)
 	public Object sessionDataSerializer() {
 		return new PdxSerializableSessionSerializer();
 	}
 
 	@Bean(SESSION_PDX_SERIALIZER_BEAN_NAME)
-	@Conditional(PdxSerializableSessionSerializerCondition.class)
+	//@Conditional(PdxSerializableSessionSerializerCondition.class)
 	public Object sessionPdxSerializer() {
 		return new DataSerializableSessionSerializer();
 	}
@@ -683,6 +700,15 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 
 		@Override
 		public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
+
+			System.err.printf("%1$s-System.getProperty(%2$s) = '%3$s'%n", getClass().getSimpleName(),
+				SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME,
+					System.getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
+
+			System.err.printf("%1$s-Environment.get(%2$s) = '%3$s'%n", getClass().getSimpleName(),
+				SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME,
+					context.getEnvironment().getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
+
 			return SESSION_DATA_SERIALIZER_BEAN_NAME
 				.equals(context.getEnvironment().getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
 		}
@@ -692,6 +718,15 @@ public class GemFireHttpSessionConfiguration extends SpringHttpSessionConfigurat
 
 		@Override
 		public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
+
+			System.err.printf("%1$s-System.getProperty(%2$s) = '%3$s'%n", getClass().getSimpleName(),
+				SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME,
+					System.getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
+
+			System.err.printf("%1$s-Environment.get(%2$s) = '%3$s'%n", getClass().getSimpleName(),
+				SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME,
+					context.getEnvironment().getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
+
 			return SESSION_PDX_SERIALIZER_BEAN_NAME
 				.equals(context.getEnvironment().getProperty(SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME));
 		}

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/SessionSerializer.java

@@ -27,28 +27,6 @@ import java.util.Optional;
  */
 public interface SessionSerializer<T, IN, OUT> {
 
-	/**
-	 * Determines whether the given {@link Object} can be de/serialized by this {@link SessionSerializer}.
-	 *
-	 * @param obj {@link Object} to evaluate for whether de/serialization is supported.
-	 * @return a boolean value indicating whether the specified {@link Object} can be de/serialized
-	 * by this {@link SessionSerializer}.
-	 * @see #canSerialize(Class)
-	 */
-	default boolean canSerialize(Object obj) {
-		return Optional.ofNullable(obj).map(Object::getClass).map(this::canSerialize).orElse(false);
-	}
-
-	/**
-	 * Determines whether the given {@link Class type} can be de/serialized by this {@link SessionSerializer}.
-	 *
-	 * @param type {@link Class} to evaluate for whether de/serialization is supported.
-	 * @return a boolean value indicating whether the specified {@link Class type} can be de/serialized
-	 * by this {@link SessionSerializer}.
-	 * @see #canSerialize(Object)
-	 */
-	boolean canSerialize(Class<?> type);
-
 	/**
 	 * Serializes the given {@link Object} to the provided {@code out} stream.
 	 *
@@ -65,4 +43,26 @@ public interface SessionSerializer<T, IN, OUT> {
 	 */
 	T deserialize(IN in);
 
+	/**
+	 * Determines whether the given {@link Class type} can be de/serialized by this {@link SessionSerializer}.
+	 *
+	 * @param type {@link Class} to evaluate for whether de/serialization is supported.
+	 * @return a boolean value indicating whether the specified {@link Class type} can be de/serialized
+	 * by this {@link SessionSerializer}.
+	 * @see #canSerialize(Object)
+	 */
+	boolean canSerialize(Class<?> type);
+
+	/**
+	 * Determines whether the given {@link Object} can be de/serialized by this {@link SessionSerializer}.
+	 *
+	 * @param obj {@link Object} to evaluate for whether de/serialization is supported.
+	 * @return a boolean value indicating whether the specified {@link Object} can be de/serialized
+	 * by this {@link SessionSerializer}.
+	 * @see #canSerialize(Class)
+	 */
+	default boolean canSerialize(Object obj) {
+		return Optional.ofNullable(obj).map(Object::getClass).map(this::canSerialize).orElse(false);
+	}
+
 }

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/data/AbstractDataSerializableSessionSerializer.java

@@ -42,6 +42,8 @@ import org.springframework.session.data.gemfire.serialization.SessionSerializer;
 public abstract class AbstractDataSerializableSessionSerializer<T> extends DataSerializer
 		implements SessionSerializer<T, DataInput, DataOutput> {
 
+	protected static final boolean DEFAULT_ALLOW_JAVA_SERIALIZATION = true;
+
 	@Override
 	public int getId() {
 		return 0x0A11ACE5;
@@ -52,6 +54,10 @@ public abstract class AbstractDataSerializableSessionSerializer<T> extends DataS
 		return new Class[0];
 	}
 
+	protected boolean allowJavaSerialization() {
+		return DEFAULT_ALLOW_JAVA_SERIALIZATION;
+	}
+
 	@Override
 	@SuppressWarnings("unchecked")
 	public boolean canSerialize(Class<?> type) {
@@ -72,11 +78,23 @@ public abstract class AbstractDataSerializableSessionSerializer<T> extends DataS
 			.orElse(false);
 	}
 
+	public void serializeObject(Object obj, DataOutput out) throws IOException {
+		serializeObject(obj, out, allowJavaSerialization());
+	}
+
+	public void serializeObject(Object obj, DataOutput out, boolean allowJavaSerialization) throws IOException {
+		writeObject(obj, out, allowJavaSerialization);
+	}
+
 	@Override
 	public Object fromData(DataInput in) throws IOException, ClassNotFoundException {
 		return deserialize(in);
 	}
 
+	public <T> T deserializeObject(DataInput in) throws ClassNotFoundException, IOException {
+		return DataSerializer.readObject(in);
+	}
+
 	protected <T> T safeRead(DataInput in, DataInputReader<T> reader) {
 		try {
 			return reader.doRead(in);

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/data/provider/DataSerializableSessionAttributesSerializer.java

@@ -24,8 +24,6 @@ import java.io.DataInput;
 import java.io.DataOutput;
 import java.util.Set;
 
-import org.apache.geode.DataSerializer;
-
 import org.springframework.session.data.gemfire.serialization.data.AbstractDataSerializableSessionSerializer;
 
 /**
@@ -64,8 +62,10 @@ public class DataSerializableSessionAttributesSerializer
 
 			attributeNames.forEach(attributeName -> {
 				safeWrite(out, output -> output.writeUTF(attributeName));
-				safeWrite(out, output -> writeObject(sessionAttributes.getAttribute(attributeName), output));
+				safeWrite(out, output -> serializeObject(sessionAttributes.getAttribute(attributeName), output));
 			});
+
+			sessionAttributes.clearDelta();
 		}
 	}
 
@@ -75,9 +75,11 @@ public class DataSerializableSessionAttributesSerializer
 		GemFireSessionAttributes sessionAttributes = GemFireSessionAttributes.create();
 
 		for (int count = safeRead(in, DataInput::readInt); count > 0; count--) {
-			sessionAttributes.setAttribute(safeRead(in, DataInput::readUTF), safeRead(in, DataSerializer::readObject));
+			sessionAttributes.setAttribute(safeRead(in, DataInput::readUTF), safeRead(in, this::deserializeObject));
 		}
 
+		sessionAttributes.clearDelta();
+
 		return sessionAttributes;
 	}
 }

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/data/provider/DataSerializableSessionSerializer.java

@@ -25,8 +25,6 @@ import java.time.Instant;
 import java.util.Collections;
 import java.util.Set;
 
-import org.apache.geode.DataSerializer;
-
 import org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession;
 import org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes;
 import org.springframework.session.data.gemfire.serialization.data.AbstractDataSerializableSessionSerializer;
@@ -78,7 +76,10 @@ public class DataSerializableSessionSerializer extends AbstractDataSerializableS
 				safeWrite(out, output -> output.writeUTF(principalName));
 			}
 
-			safeWrite(out, output -> writeObject(session.getAttributes(), out));
+			safeWrite(out, output -> serializeObject(session.getAttributes(), out));
+
+			session.clearDelta();
+			session.getAttributes().clearDelta();
 		}
 	}
 
@@ -119,7 +120,9 @@ public class DataSerializableSessionSerializer extends AbstractDataSerializableS
 			session.setPrincipalName(safeRead(in, DataInput::readUTF));
 		}
 
-		session.getAttributes().from(this.<GemFireSessionAttributes>safeRead(in, DataSerializer::readObject));
+		session.getAttributes().from(this.<GemFireSessionAttributes>safeRead(in, this::deserializeObject));
+		session.getAttributes().clearDelta();
+		session.clearDelta();
 
 		return session;
 	}

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/pdx/provider/PdxSerializableSessionSerializer.java

@@ -17,11 +17,12 @@
 package org.springframework.session.data.gemfire.serialization.pdx.provider;
 
 import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession;
-import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes;
 
 import java.time.Duration;
 import java.time.Instant;
 import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 
@@ -56,11 +57,16 @@ public class PdxSerializableSessionSerializer extends AbstractPdxSerializableSes
 			writer.writeLong("lastAccessedTime", session.getLastAccessedTime().toEpochMilli());
 			writer.writeLong("maxInactiveIntervalInSeconds", session.getMaxInactiveInterval().getSeconds());
 			writer.writeString("principalName", session.getPrincipalName());
-			writer.writeObject("attributes", session.getAttributes());
+			writer.writeObject("attributes", newMap(session.getAttributes()));
 		}
 	}
 
+	protected <K, V> Map<K, V> newMap(Map<K, V> map) {
+		return new HashMap<>(map);
+	}
+
 	@Override
+	@SuppressWarnings("unchecked")
 	public GemFireSession deserialize(PdxReader reader) {
 
 		GemFireSession session = GemFireSession.from(new AbstractSession() {
@@ -92,7 +98,7 @@ public class PdxSerializableSessionSerializer extends AbstractPdxSerializableSes
 		});
 
 		session.setPrincipalName(reader.readString("principalName"));
-		session.getAttributes().from((GemFireSessionAttributes) reader.readObject("attributes"));
+		session.getAttributes().from((Map<String, Object>) reader.readObject("attributes"));
 
 		return session;
 	}

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/serialization/pdx/support/ComposablePdxSerializer.java

@@ -25,6 +25,7 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
@@ -57,7 +58,8 @@ public class ComposablePdxSerializer implements Iterable<PdxSerializer>, PdxSeri
 	public static PdxSerializer compose(Iterable<PdxSerializer> pdxSerializers) {
 
 		List<PdxSerializer> pdxSerializerList =
-			stream(nullSafeIterable(pdxSerializers).spliterator(), false).collect(Collectors.toList());
+			stream(nullSafeIterable(pdxSerializers).spliterator(), false)
+				.filter(Objects::nonNull).collect(Collectors.toList());
 
 		return (pdxSerializerList.isEmpty() ? null
 			: (pdxSerializerList.size() == 1 ? pdxSerializerList.get(0)

spring-session-data-geode/src/main/java/org/springframework/session/data/gemfire/support/AbstractSession.java

@@ -23,80 +23,84 @@ import java.util.Set;
 import org.springframework.session.Session;
 
 /**
- * The AbstractSession class...
+ * The {@link AbstractSession} abstract class is a base implementation of the {@link Session} interface
+ * to simplify the implementation of various {@link Session} types and their capabilities.
  *
  * @author John Blum
- * @since 1.0.0
+ * @see org.springframework.session.data.gemfire.support.AbstractSession
+ * @since 2.0.0
  */
 public class AbstractSession implements Session {
 
+	public static final String NOT_IMPLEMENTED = "Not Implemented";
+
 	@Override
 	public String getId() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public void setAttribute(String attributeName, Object attributeValue) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public <T> T getAttribute(String attributeName) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public <T> T getAttributeOrDefault(String name, T defaultValue) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public <T> T getRequiredAttribute(String name) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public Set<String> getAttributeNames() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public boolean isExpired() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public Instant getCreationTime() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public void setLastAccessedTime(Instant lastAccessedTime) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public Instant getLastAccessedTime() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public void setMaxInactiveInterval(Duration interval) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public Duration getMaxInactiveInterval() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public String changeSessionId() {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 
 	@Override
 	public void removeAttribute(String attributeName) {
-		throw new UnsupportedOperationException("Not Implemented");
+		throw new UnsupportedOperationException(NOT_IMPLEMENTED);
 	}
 }

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/AbstractGemFireOperationsSessionRepositoryTests.java

@@ -33,13 +33,14 @@ import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
+import static org.springframework.data.gemfire.util.CollectionUtils.asSet;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.DeltaCapableGemFireSession;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.DeltaCapableGemFireSessionAttributes;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes;
 
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
 import java.io.DataInput;
-import java.io.DataInputStream;
 import java.io.DataOutput;
-import java.io.DataOutputStream;
 import java.io.IOException;
 import java.time.Duration;
 import java.time.Instant;
@@ -104,7 +105,7 @@ import org.apache.commons.logging.Log;
  * @see edu.umd.cs.mtc.TestFramework
  */
 @RunWith(MockitoJUnitRunner.class)
-public class AbstractGemFireOperationsSessionRepositoryTest {
+public class AbstractGemFireOperationsSessionRepositoryTests {
 
 	protected static final int MAX_INACTIVE_INTERVAL_IN_SECONDS = 600;
 
@@ -123,20 +124,11 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 			@Override
 			Log newLogger() {
-				return AbstractGemFireOperationsSessionRepositoryTest.this.mockLog;
+				return mockLog;
 			}
 		});
 	}
 
-	private static <E> Set<E> asSet(E... elements) {
-
-		Set<E> set = new HashSet<>(elements.length);
-
-		Collections.addAll(set, elements);
-
-		return set;
-	}
-
 	@SuppressWarnings("unchecked")
 	protected <K, V> EntryEvent<K, V> mockEntryEvent(Operation operation, K key, V oldValue, V newValue) {
 
@@ -151,11 +143,11 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	}
 
 	@SuppressWarnings("unchecked")
-	protected <K, V> Region mockRegion(String name, DataPolicy dataPolicy) {
+	protected <K, V> Region<K, V> mockRegion(String name, DataPolicy dataPolicy) {
 
 		Region<K, V> mockRegion = mock(Region.class, name);
 
-		RegionAttributes<K, V> mockRegionAttributes = mock(RegionAttributes.class);
+		RegionAttributes<K, V> mockRegionAttributes = mockRegionAttributes(name);
 
 		given(mockRegion.getAttributes()).willReturn(mockRegionAttributes);
 		given(mockRegionAttributes.getDataPolicy()).willReturn(dataPolicy);
@@ -163,6 +155,11 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		return mockRegion;
 	}
 
+	@SuppressWarnings("unchecked")
+	protected <K, V> RegionAttributes<K, V> mockRegionAttributes(String name) {
+		return mock(RegionAttributes.class, name);
+	}
+
 	protected Session mockSession(String sessionId, long creationAndLastAccessedTime,
 			long maxInactiveIntervalInSeconds) {
 
@@ -387,7 +384,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isEqualTo(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -430,7 +427,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -553,7 +550,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isEqualTo(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -593,7 +590,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -632,7 +629,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -674,7 +671,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isEqualTo(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -713,7 +710,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -752,7 +749,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -802,7 +799,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 				AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 				assertThat(sessionEvent.getSource())
-					.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+					.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 				assertThat(sessionEvent.<Session>getSession()).isEqualTo(mockSession);
 				assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -874,7 +871,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isEqualTo(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -906,7 +903,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
-			assertThat(sessionEvent.getSource()).isEqualTo(AbstractGemFireOperationsSessionRepositoryTest.this.sessionRepository);
+			assertThat(sessionEvent.getSource()).isEqualTo(AbstractGemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(sessionId);
 
@@ -956,8 +953,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Instant beforeOrAtCreationTime = Instant.now();
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession();
+		GemFireSession session = new GemFireSession();
 
 		assertThat(session.getId()).isNotNull();
 		assertThat(session.getCreationTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
@@ -972,8 +968,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Instant beforeOrAtCreationTime = Instant.now();
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1");
+		GemFireSession session = new GemFireSession("1");
 
 		assertThat(session.getId()).isEqualTo("1");
 		assertThat(session.getCreationTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
@@ -986,7 +981,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test(expected = IllegalArgumentException.class)
 	public void constructGemFireSessionWithUnspecifiedId() {
 		try {
-			new AbstractGemFireOperationsSessionRepository.GemFireSession(" ");
+			new GemFireSession(" ");
 		}
 		catch (IllegalArgumentException expected) {
 			assertThat(expected).hasMessage("ID is required");
@@ -1013,8 +1008,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		given(mockSession.getAttribute(eq("attrOne"))).willReturn("testOne");
 		given(mockSession.getAttribute(eq("attrTwo"))).willReturn("testTwo");
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession gemfireSession =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession(mockSession);
+		GemFireSession gemfireSession = new GemFireSession(mockSession);
 
 		assertThat(gemfireSession.getId()).isEqualTo("2");
 		assertThat(gemfireSession.getCreationTime()).isEqualTo(expectedCreationTime);
@@ -1036,7 +1030,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test(expected = IllegalArgumentException.class)
 	public void constructGemFireSessionWithNullSession() {
 		try {
-			new AbstractGemFireOperationsSessionRepository.GemFireSession((Session) null);
+			new GemFireSession((Session) null);
 		}
 		catch (IllegalArgumentException expected) {
 			assertThat(expected).hasMessage("The Session to copy cannot be null");
@@ -1053,8 +1047,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Duration maxInactiveInterval = Duration.ofSeconds(120L);
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(maxInactiveInterval);
+		GemFireSession<?> session = GemFireSession.create(maxInactiveInterval);
 
 		assertThat(session).isNotNull();
 		assertThat(session.getId()).isNotNull();
@@ -1062,7 +1055,23 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		assertThat(session.getLastAccessedTime()).isEqualTo(session.getCreationTime());
 		assertThat(session.getMaxInactiveInterval()).isEqualTo(maxInactiveInterval);
 		assertThat(session.getAttributeNames()).isNotNull();
-		assertThat(session.getAttributeNames().isEmpty()).isTrue();
+		assertThat(session.getAttributeNames()).isEmpty();
+	}
+
+	@Test
+	public void createNewGemFireSessionWithDefaultMaxInactiveInterval() {
+
+		Instant beforeOrAtCreationTime = Instant.now();
+
+		GemFireSession<?> session = GemFireSession.create();
+
+		assertThat(session).isNotNull();
+		assertThat(session.getId()).isNotNull();
+		assertThat(session.getCreationTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
+		assertThat(session.getLastAccessedTime()).isEqualTo(session.getCreationTime());
+		assertThat(session.getMaxInactiveInterval()).isEqualTo(GemFireSession.DEFAULT_MAX_INACTIVE_INTERVAL);
+		assertThat(session.getAttributeNames()).isNotNull();
+		assertThat(session.getAttributeNames()).isEmpty();
 	}
 
 	@Test
@@ -1078,8 +1087,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		given(mockSession.getAttributeNames()).willReturn(Collections.emptySet());
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession gemfireSession =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.from(mockSession);
+		GemFireSession<?> gemfireSession = GemFireSession.from(mockSession);
 
 		assertThat(gemfireSession).isNotNull();
 		assertThat(gemfireSession.getId()).isEqualTo("4");
@@ -1100,11 +1108,9 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void fromExistingGemFireSessionIsGemFireSession() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession gemfireSession =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(Duration.ofSeconds(300));
+		GemFireSession<?> gemfireSession = GemFireSession.create();
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession fromGemFireSession =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.from(gemfireSession);
+		GemFireSession<?> fromGemFireSession = GemFireSession.from(gemfireSession);
 
 		assertThat(fromGemFireSession).isSameAs(gemfireSession);
 	}
@@ -1112,12 +1118,10 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void setGetAndRemoveAttribute() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(Duration.ofSeconds(60));
+		GemFireSession<?> session = GemFireSession.create();
 
 		assertThat(session).isNotNull();
-		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(60));
-		assertThat(session.getAttributeNames().isEmpty()).isTrue();
+		assertThat(session.getAttributeNames()).isEmpty();
 
 		session.setAttribute("attrOne", "testOne");
 
@@ -1149,8 +1153,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Duration expectedMaxInactiveIntervalInSeconds = Duration.ofSeconds(-1);
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(expectedMaxInactiveIntervalInSeconds);
+		GemFireSession<?> session = GemFireSession.create(expectedMaxInactiveIntervalInSeconds);
 
 		assertThat(session).isNotNull();
 		assertThat(session.getMaxInactiveInterval()).isEqualTo(expectedMaxInactiveIntervalInSeconds);
@@ -1162,8 +1165,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Duration expectedMaxInactiveIntervalInSeconds = Duration.ZERO;
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(expectedMaxInactiveIntervalInSeconds);
+		GemFireSession<?> session = GemFireSession.create(expectedMaxInactiveIntervalInSeconds);
 
 		assertThat(session).isNotNull();
 		assertThat(session.getMaxInactiveInterval()).isEqualTo(expectedMaxInactiveIntervalInSeconds);
@@ -1175,12 +1177,11 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		long expectedMaxInactiveIntervalInSeconds = TimeUnit.HOURS.toSeconds(2);
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(
-				Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
+		GemFireSession<?> session = GemFireSession.create(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
 
 		assertThat(session).isNotNull();
-		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
+		assertThat(session.getMaxInactiveInterval())
+			.isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
 
 		Instant now = Instant.now();
 
@@ -1195,12 +1196,11 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		int expectedMaxInactiveIntervalInSeconds = 60;
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(
-				Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
+		GemFireSession<?> session = GemFireSession.create(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
 
 		assertThat(session).isNotNull();
-		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
+		assertThat(session.getMaxInactiveInterval())
+			.isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
 
 		Instant twoHoursAgo = Instant.ofEpochMilli(System.currentTimeMillis() - TimeUnit.HOURS.toMillis(2));
 
@@ -1213,8 +1213,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void setAndGetPrincipalName() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			AbstractGemFireOperationsSessionRepository.GemFireSession.create(Duration.ZERO);
+		GemFireSession<?> session = GemFireSession.create(Duration.ZERO);
 
 		assertThat(session).isNotNull();
 		assertThat(session.getPrincipalName()).isNull();
@@ -1236,141 +1235,6 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		assertThat(session.getPrincipalName()).isNull();
 	}
 
-	@Test
-	public void sessionToData() throws Exception {
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1") {
-
-				@Override
-				void writeObject(Object obj, DataOutput out) throws IOException {
-					assertThat(obj).isInstanceOf(AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes.class);
-					assertThat(out).isNotNull();
-			}
-		};
-
-		session.setLastAccessedTime(Instant.ofEpochMilli(123L));
-		session.setMaxInactiveInterval(Duration.ofSeconds(MAX_INACTIVE_INTERVAL_IN_SECONDS));
-		session.setPrincipalName("jblum");
-
-		DataOutput mockDataOutput = mock(DataOutput.class);
-
-		session.toData(mockDataOutput);
-
-		verify(mockDataOutput, times(1)).writeUTF(eq("1"));
-		verify(mockDataOutput, times(1)).writeLong(eq(session.getCreationTime().toEpochMilli()));
-		verify(mockDataOutput, times(1)).writeLong(eq(session.getLastAccessedTime().toEpochMilli()));
-		verify(mockDataOutput, times(1)).writeLong(eq(session.getMaxInactiveInterval().getSeconds()));
-		verify(mockDataOutput, times(1)).writeInt(eq("jblum".length()));
-		verify(mockDataOutput, times(1)).writeUTF(eq(session.getPrincipalName()));
-	}
-
-	@Test
-	public void sessionFromData() throws Exception {
-
-		long expectedCreationTime = 1L;
-		long expectedLastAccessedTime = 2L;
-		long expectedMaxInactiveIntervalInSeconds = TimeUnit.HOURS.toSeconds(6);
-
-		String expectedPrincipalName = "jblum";
-		String expectedSessionId = "2";
-
-		DataInput mockDataInput = mock(DataInput.class);
-
-		given(mockDataInput.readUTF()).willReturn(expectedSessionId).willReturn(expectedPrincipalName);
-		given(mockDataInput.readLong()).willReturn(expectedCreationTime).willReturn(expectedLastAccessedTime)
-			.willReturn(expectedMaxInactiveIntervalInSeconds);
-		given(mockDataInput.readInt()).willReturn(expectedPrincipalName.length());
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1") {
-
-				@Override
-				@SuppressWarnings("unchecked")
-				<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-
-					assertThat(in).isNotNull();
-
-					AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-						new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
-
-					sessionAttributes.setAttribute("attrOne", "testOne");
-					sessionAttributes.setAttribute("attrTwo", "testTwo");
-
-					return (T) sessionAttributes;
-				}
-		};
-
-		session.fromData(mockDataInput);
-
-		Set<String> expectedAttributeNames =
-			asSet("attrOne", "attrTwo", FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME);
-
-		assertThat(session.getId()).isEqualTo(expectedSessionId);
-		assertThat(session.getCreationTime()).isEqualTo(Instant.ofEpochMilli(expectedCreationTime));
-		assertThat(session.getLastAccessedTime()).isEqualTo(Instant.ofEpochMilli(expectedLastAccessedTime));
-		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
-		assertThat(session.getPrincipalName()).isEqualTo(expectedPrincipalName);
-		assertThat(session.getAttributeNames()).hasSize(3);
-		assertThat(session.getAttributeNames()).containsAll(expectedAttributeNames);
-		assertThat(session.<String>getAttribute("attrOne")).isEqualTo("testOne");
-		assertThat(session.<String>getAttribute("attrTwo")).isEqualTo("testTwo");
-		assertThat(session.<String>getAttribute(FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME))
-			.isEqualTo(expectedPrincipalName);
-
-		verify(mockDataInput, times(2)).readUTF();
-		verify(mockDataInput, times(3)).readLong();
-		verify(mockDataInput, times(1)).readInt();
-	}
-
-	@Test
-	public void sessionToDataThenFromDataWhenPrincipalNameIsNullGetsHandledProperly()
-			throws ClassNotFoundException, IOException {
-
-		Instant beforeOrAtCreationTime = Instant.now();
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession expectedSession =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("123") {
-
-				@Override
-				void writeObject(Object obj, DataOutput out) throws IOException {
-					assertThat(obj).isInstanceOf(AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes.class);
-					assertThat(out).isNotNull();
-				}
-		};
-
-		assertThat(expectedSession.getId()).isEqualTo("123");
-		assertThat(expectedSession.getCreationTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
-		assertThat(expectedSession.getLastAccessedTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
-		assertThat(expectedSession.getMaxInactiveInterval()).isEqualTo(Duration.ZERO);
-		assertThat(expectedSession.getPrincipalName()).isNull();
-
-		ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
-
-		expectedSession.toData(new DataOutputStream(outBytes));
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession deserializedSession =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("0") {
-				@Override
-				@SuppressWarnings("unchecked")
-				<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-					return (T) new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
-				}
-		};
-
-		deserializedSession.fromData(new DataInputStream(new ByteArrayInputStream(outBytes.toByteArray())));
-
-		assertThat(deserializedSession).isEqualTo(expectedSession);
-		assertThat(deserializedSession.getCreationTime()).isEqualTo(expectedSession.getCreationTime());
-		assertThat(deserializedSession.getLastAccessedTime()).isEqualTo(expectedSession.getLastAccessedTime());
-		assertThat(deserializedSession.getMaxInactiveInterval()).isEqualTo(expectedSession.getMaxInactiveInterval());
-		assertThat(deserializedSession.getPrincipalName()).isNull();
-	}
-
 	@Test
 	public void hasDeltaWhenNoSessionChangesIsFalse() {
 		assertThat(new AbstractGemFireOperationsSessionRepository.GemFireSession().hasDelta()).isFalse();
@@ -1379,8 +1243,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void hasDeltaWhenSessionAttributesChangeIsTrue() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession();
+		GemFireSession session = new DeltaCapableGemFireSession();
 
 		assertThat(session.hasDelta()).isFalse();
 
@@ -1439,15 +1302,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		DataOutput mockDataOutput = mock(DataOutput.class);
 
 		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession() {
-
-				@Override
-				void writeObject(Object obj, DataOutput out) throws IOException {
-					assertThat(String.valueOf(obj)).isEqualTo("test");
-					assertThat(out).isSameAs(mockDataOutput);
-				}
-		};
+		DeltaCapableGemFireSession session = new DeltaCapableGemFireSession();
 
 		session.setLastAccessedTime(Instant.ofEpochMilli(1L));
 		session.setMaxInactiveInterval(Duration.ofSeconds(300L));
@@ -1470,31 +1325,24 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		DataInput mockDataInput = mock(DataInput.class);
 
+		given(mockDataInput.readUTF()).willReturn("1");
 		given(mockDataInput.readLong()).willReturn(1L).willReturn(600L);
 		given(mockDataInput.readInt()).willReturn(0);
 
 		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession() {
-
-				@Override
-				@SuppressWarnings("unchecked")
-				<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-					assertThat(in).isSameAs(mockDataInput);
-					return (T) "test";
-				}
-		};
+		DeltaCapableGemFireSession session = new DeltaCapableGemFireSession();
 
 		session.fromDelta(mockDataInput);
 
 		assertThat(session.hasDelta()).isFalse();
+		assertThat(session.getId()).isEqualTo("1");
 		assertThat(session.getLastAccessedTime()).isEqualTo(Instant.ofEpochMilli(1L));
 		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(600L));
 		assertThat(session.getAttributeNames().isEmpty()).isTrue();
 
+		verify(mockDataInput, times(1)).readUTF();
 		verify(mockDataInput, times(2)).readLong();
 		verify(mockDataInput, times(1)).readInt();
-		verify(mockDataInput, never()).readUTF();
 	}
 
 	@Test
@@ -1502,12 +1350,10 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		Instant twoHoursAgo = Instant.now().minusMillis(TimeUnit.HOURS.toMillis(2));
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession sessionOne =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession(
-				mockSession("1", twoHoursAgo.toEpochMilli(), MAX_INACTIVE_INTERVAL_IN_SECONDS));
+		GemFireSession<?> sessionOne =
+			new GemFireSession<>(mockSession("1", twoHoursAgo.toEpochMilli(), MAX_INACTIVE_INTERVAL_IN_SECONDS));
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession sessionTwo =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("2");
+		GemFireSession<?> sessionTwo = new GemFireSession<>("2");
 
 		assertThat(sessionOne.getCreationTime()).isEqualTo(twoHoursAgo);
 		assertThat(sessionTwo.getCreationTime().isAfter(twoHoursAgo)).isTrue();
@@ -1519,15 +1365,13 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void sessionEqualsDifferentSessionBasedOnId() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession sessionOne =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1");
+		GemFireSession sessionOne = new GemFireSession("1");
 
 		sessionOne.setLastAccessedTime(Instant.ofEpochSecond(12345L));
 		sessionOne.setMaxInactiveInterval(Duration.ofSeconds(120L));
 		sessionOne.setPrincipalName("jblum");
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession sessionTwo =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1");
+		GemFireSession sessionTwo = new GemFireSession("1");
 
 		sessionTwo.setLastAccessedTime(Instant.ofEpochSecond(67890L));
 		sessionTwo.setMaxInactiveInterval(Duration.ofSeconds(300L));
@@ -1543,8 +1387,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void sessionHashCodeIsNotEqualToStringIdHashCode() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSession session =
-			new AbstractGemFireOperationsSessionRepository.GemFireSession("1");
+		GemFireSession session = new GemFireSession("1");
 
 		assertThat(session.getId()).isEqualTo("1");
 		assertThat(session.hashCode()).isNotEqualTo("1".hashCode());
@@ -1559,8 +1402,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		given(mockSession.getAttribute(eq("attrOne"))).willReturn("testOne");
 		given(mockSession.getAttribute(eq("attrTwo"))).willReturn("testTwo");
 
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
+		GemFireSessionAttributes sessionAttributes = new GemFireSessionAttributes();
 
 		assertThat(sessionAttributes.getAttributeNames().isEmpty()).isTrue();
 
@@ -1585,8 +1427,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		source.setAttribute("attrOne", "testOne");
 		source.setAttribute("attrTwo", "testTwo");
 
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes target =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
+		GemFireSessionAttributes target = new GemFireSessionAttributes();
 
 		assertThat(target.getAttributeNames().isEmpty()).isTrue();
 
@@ -1598,69 +1439,6 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		assertThat(target.<String>getAttribute("attrTwo")).isEqualTo("testTwo");
 	}
 
-	@Test
-	public void sessionAttributesToData() throws Exception {
-
-		DataOutput mockDataOutput = mock(DataOutput.class);
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes() {
-
-				private int count = 0;
-
-				@Override
-				void writeObject(Object obj, DataOutput out) throws IOException {
-					assertThat(Arrays.asList("testOne", "testTwo").get(count++)).isEqualTo(String.valueOf(obj));
-					assertThat(out).isSameAs(mockDataOutput);
-				}
-		};
-
-		sessionAttributes.setAttribute("attrOne", "testOne");
-		sessionAttributes.setAttribute("attrTwo", "testTwo");
-
-		sessionAttributes.toData(mockDataOutput);
-
-		verify(mockDataOutput, times(1)).writeInt(eq(2));
-		verify(mockDataOutput, times(1)).writeUTF(eq("attrOne"));
-		verify(mockDataOutput, times(1)).writeUTF(eq("attrTwo"));
-	}
-
-	@Test
-	public void sessionAttributesFromData() throws Exception {
-
-		DataInput mockDataInput = mock(DataInput.class);
-
-		given(mockDataInput.readInt()).willReturn(2);
-		given(mockDataInput.readUTF()).willReturn("attrOne").willReturn("attrTwo");
-
-		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes() {
-
-				private int count = 0;
-
-				@Override
-				@SuppressWarnings("unchecked")
-				<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
-					assertThat(in).isSameAs(mockDataInput);
-					return (T) Arrays.asList("testOne", "testTwo").get(count++);
-				}
-		};
-
-		assertThat(sessionAttributes.getAttributeNames().isEmpty()).isTrue();
-
-		sessionAttributes.fromData(mockDataInput);
-
-		assertThat(sessionAttributes.getAttributeNames().size()).isEqualTo(2);
-		assertThat(sessionAttributes.getAttributeNames().containsAll(asSet("attrOne", "attrTwo"))).isTrue();
-		assertThat(sessionAttributes.<String>getAttribute("attrOne")).isEqualTo("testOne");
-		assertThat(sessionAttributes.<String>getAttribute("attrTwo")).isEqualTo("testTwo");
-
-		verify(mockDataInput, times(1)).readInt();
-		verify(mockDataInput, times(2)).readUTF();
-	}
-
 	@Test
 	public void sessionAttributesHasDeltaIsFalse() {
 		assertThat(new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes().hasDelta()).isFalse();
@@ -1669,8 +1447,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void sessionAttributesHasDeltaIsTrue() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
+		GemFireSessionAttributes sessionAttributes = new DeltaCapableGemFireSessionAttributes();
 
 		assertThat(sessionAttributes.hasDelta()).isFalse();
 
@@ -1686,13 +1463,12 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		DataOutput mockDataOutput = mock(DataOutput.class);
 
 		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes() {
+		DeltaCapableGemFireSessionAttributes sessionAttributes = new DeltaCapableGemFireSessionAttributes() {
 
 				private int count = 0;
 
 				@Override
-				void writeObject(Object obj, DataOutput out) throws IOException {
+				protected void writeObject(Object obj, DataOutput out) throws IOException {
 					assertThat(Arrays.asList("testOne", "testTwo", "testThree").get(count++)).isEqualTo(String.valueOf(obj));
 					assertThat(out).isSameAs(mockDataOutput);
 				}
@@ -1741,14 +1517,13 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		given(mockDataInput.readUTF()).willReturn("attrOne").willReturn("attrTwo");
 
 		@SuppressWarnings("serial")
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes() {
+		DeltaCapableGemFireSessionAttributes sessionAttributes = new DeltaCapableGemFireSessionAttributes() {
 
 				private int count = 0;
 
 				@Override
 				@SuppressWarnings("unchecked")
-				<T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
+				protected <T> T readObject(DataInput in) throws ClassNotFoundException, IOException {
 					assertThat(in).isSameAs(mockDataInput);
 					return (T) Arrays.asList("testOne", "testTwo", "testThree").get(count++);
 				}
@@ -1802,8 +1577,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@Test
 	public void sessionAttributesEntrySetIteratesAttributeNameValues() {
 
-		AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes sessionAttributes =
-			new AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes();
+		GemFireSessionAttributes sessionAttributes = new GemFireSessionAttributes();
 
 		sessionAttributes.setAttribute("keyOne", "valueOne");
 		sessionAttributes.setAttribute("keyTwo", "valueTwo");
@@ -1813,8 +1587,8 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		assertThat(sessionAttributeEntries).isNotNull();
 		assertThat(sessionAttributeEntries.size()).isEqualTo(2);
 
-		Set<String> expectedNames = asSet("keyOne", "keyTwo");
-		Set<?> expectedValues = asSet("valueOne", "valueTwo");
+		Set<String> expectedNames = new HashSet<>(asSet("keyOne", "keyTwo"));
+		Set<?> expectedValues = new HashSet<>(asSet("valueOne", "valueTwo"));
 
 		for (Map.Entry<String, Object> entry : sessionAttributeEntries) {
 			expectedNames.remove(entry.getKey());
@@ -1828,8 +1602,8 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 
 		assertThat(sessionAttributeEntries.size()).isEqualTo(3);
 
-		expectedNames = asSet("keyOne", "keyTwo");
-		expectedValues = asSet("valueOne", "valueTwo");
+		expectedNames = new HashSet<>(asSet("keyOne", "keyTwo"));
+		expectedValues = new HashSet<>(asSet("valueOne", "valueTwo"));
 
 		for (Map.Entry<String, Object> entry : sessionAttributeEntries) {
 			expectedNames.remove(entry.getKey());
@@ -1858,7 +1632,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 	@SuppressWarnings("unused")
 	protected static final class ThreadSafeSessionTest extends MultithreadedTestCase {
 
-		private AbstractGemFireOperationsSessionRepository.GemFireSession session;
+		private GemFireSession<?> session;
 
 		private final Instant beforeOrAtCreationTime = Instant.now();
 
@@ -1867,7 +1641,7 @@ public class AbstractGemFireOperationsSessionRepositoryTest {
 		@Override
 		public void initialize() {
 
-			this.session = new AbstractGemFireOperationsSessionRepository.GemFireSession("1");
+			this.session = new GemFireSession<>("1");
 
 			assertThat(this.session).isNotNull();
 			assertThat(this.session.getId()).isEqualTo("1");

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/GemFireOperationsSessionRepositoryTests.java

@@ -74,7 +74,7 @@ import org.springframework.session.events.SessionDeletedEvent;
  * @see org.springframework.session.data.gemfire.GemFireOperationsSessionRepository
  */
 @RunWith(MockitoJUnitRunner.class)
-public class GemFireOperationsSessionRepositoryTest {
+public class GemFireOperationsSessionRepositoryTests {
 
 	protected static final int MAX_INACTIVE_INTERVAL_IN_SECONDS = 600;
 
@@ -271,7 +271,7 @@ public class GemFireOperationsSessionRepositoryTest {
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
 			assertThat(sessionEvent.getSource())
-				.isSameAs(GemFireOperationsSessionRepositoryTest.this.sessionRepository);
+				.isSameAs(GemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isSameAs(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(expectedSessionId);
 
@@ -393,7 +393,7 @@ public class GemFireOperationsSessionRepositoryTest {
 
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
-			assertThat(sessionEvent.getSource()).isSameAs(GemFireOperationsSessionRepositoryTest.this.sessionRepository);
+			assertThat(sessionEvent.getSource()).isSameAs(GemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isSameAs(mockSession);
 			assertThat(sessionEvent.getSessionId()).isEqualTo(expectedSessionId);
 
@@ -423,7 +423,7 @@ public class GemFireOperationsSessionRepositoryTest {
 
 			AbstractSessionEvent sessionEvent = (AbstractSessionEvent) applicationEvent;
 
-			assertThat(sessionEvent.getSource()).isSameAs(GemFireOperationsSessionRepositoryTest.this.sessionRepository);
+			assertThat(sessionEvent.getSource()).isSameAs(GemFireOperationsSessionRepositoryTests.this.sessionRepository);
 			assertThat(sessionEvent.<Session>getSession()).isNull();
 			assertThat(sessionEvent.getSessionId()).isEqualTo(expectedSessionId);
 

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/config/annotation/web/http/GemFireHttpSessionConfigurationTests.java

@@ -28,6 +28,7 @@ import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.Map;
 
+import org.junit.AfterClass;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -41,6 +42,8 @@ import org.apache.geode.cache.RegionShortcut;
 import org.apache.geode.cache.client.ClientCache;
 import org.apache.geode.cache.client.ClientRegionShortcut;
 
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.core.type.AnnotationMetadata;
 import org.springframework.data.gemfire.GemfireOperations;
 import org.springframework.data.gemfire.GemfireTemplate;
@@ -50,26 +53,36 @@ import org.springframework.session.data.gemfire.GemFireOperationsSessionReposito
 import org.springframework.session.data.gemfire.config.annotation.web.http.support.GemFireCacheTypeAwareRegionFactoryBean;
 
 /**
- * The GemFireHttpSessionConfigurationTest class is a test suite of test cases testing the
- * contract and functionality of the {@link GemFireHttpSessionConfiguration} class.
+ * Unit tests for {@link GemFireHttpSessionConfiguration} class.
  *
  * @author John Blum
  * @since 1.1.0
  * @see org.junit.Test
  * @see org.mockito.Mockito
- * @see org.springframework.data.gemfire.GemfireOperations
- * @see org.springframework.data.gemfire.GemfireTemplate
- * @see org.springframework.session.data.gemfire.GemFireOperationsSessionRepository
- * @see org.springframework.session.data.gemfire.config.annotation.web.http.GemFireHttpSessionConfiguration
  * @see org.apache.geode.cache.Cache
  * @see org.apache.geode.cache.GemFireCache
  * @see org.apache.geode.cache.Region
+ * @see org.apache.geode.cache.ExpirationAttributes
+ * @see org.apache.geode.cache.RegionAttributes
  * @see org.apache.geode.cache.client.ClientCache
+ * @see org.springframework.beans.factory.config.ConfigurableListableBeanFactory
+ * @see org.springframework.context.ConfigurableApplicationContext
+ * @see org.springframework.core.type.AnnotationMetadata
+ * @see org.springframework.data.gemfire.GemfireOperations
+ * @see org.springframework.data.gemfire.GemfireTemplate
+ * @see org.springframework.session.Session
+ * @see org.springframework.session.data.gemfire.GemFireOperationsSessionRepository
+ * @see org.springframework.session.data.gemfire.config.annotation.web.http.GemFireHttpSessionConfiguration
  */
-public class GemFireHttpSessionConfigurationTest {
+public class GemFireHttpSessionConfigurationTests {
 
 	private GemFireHttpSessionConfiguration gemfireConfiguration;
 
+	@AfterClass
+	public static void tearDown() {
+		System.clearProperty(GemFireHttpSessionConfiguration.SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME);
+	}
+
 	@SuppressWarnings("unchecked")
 	protected <T> T getField(Object obj, String fieldName) {
 		try {
@@ -197,7 +210,7 @@ public class GemFireHttpSessionConfigurationTest {
 	}
 
 	@Test
-	public void setAndGetSpringSessionGemFireRegionName() {
+	public void setAndGetSessionRegionName() {
 
 		assertThat(this.gemfireConfiguration.getSessionRegionName()).isEqualTo(
 			GemFireHttpSessionConfiguration.DEFAULT_SESSION_REGION_NAME);
@@ -222,6 +235,61 @@ public class GemFireHttpSessionConfigurationTest {
 			GemFireHttpSessionConfiguration.DEFAULT_SESSION_REGION_NAME);
 	}
 
+	@Test
+	public void setAndGetSessionSerializerBeanName() {
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.DEFAULT_SESSION_SERIALIZER_BEAN_NAME);
+
+		this.gemfireConfiguration.setSessionSerializerBeanName(
+			GemFireHttpSessionConfiguration.SESSION_DATA_SERIALIZER_BEAN_NAME);
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.SESSION_DATA_SERIALIZER_BEAN_NAME);
+
+		this.gemfireConfiguration.setSessionSerializerBeanName(null);
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.DEFAULT_SESSION_SERIALIZER_BEAN_NAME);
+
+		this.gemfireConfiguration.setSessionSerializerBeanName(
+			GemFireHttpSessionConfiguration.SESSION_PDX_SERIALIZER_BEAN_NAME);
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.SESSION_PDX_SERIALIZER_BEAN_NAME);
+	}
+
+	@Test
+	public void isUsingDataSerializationIsFalse() {
+
+		this.gemfireConfiguration.setSessionSerializerBeanName("test");
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName()).isEqualTo("test");
+		assertThat(this.gemfireConfiguration.isUsingDataSerialization()).isFalse();
+
+		this.gemfireConfiguration.setSessionSerializerBeanName(
+			GemFireHttpSessionConfiguration.SESSION_PDX_SERIALIZER_BEAN_NAME);
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.SESSION_PDX_SERIALIZER_BEAN_NAME);
+
+		assertThat(this.gemfireConfiguration.isUsingDataSerialization()).isFalse();
+	}
+
+	@Test
+	public void isUsingDataSerializationIsTrue() {
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.SESSION_DATA_SERIALIZER_BEAN_NAME);
+		assertThat(this.gemfireConfiguration.isUsingDataSerialization()).isTrue();
+
+		this.gemfireConfiguration.setSessionSerializerBeanName(null);
+
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName())
+			.isEqualTo(GemFireHttpSessionConfiguration.SESSION_DATA_SERIALIZER_BEAN_NAME);
+		assertThat(this.gemfireConfiguration.isUsingDataSerialization()).isTrue();
+	}
+
 	@Test
 	public void setsImportMetadata() {
 
@@ -235,6 +303,7 @@ public class GemFireHttpSessionConfigurationTest {
 		annotationAttributes.put("poolName", "TestPool");
 		annotationAttributes.put("serverRegionShortcut", RegionShortcut.REPLICATE);
 		annotationAttributes.put("regionName", "TEST");
+		annotationAttributes.put("sessionSerializerBeanName", "testSessionSerializer");
 
 		given(mockAnnotationMetadata.getAnnotationAttributes(eq(EnableGemFireHttpSession.class.getName())))
 			.willReturn(annotationAttributes);
@@ -247,8 +316,36 @@ public class GemFireHttpSessionConfigurationTest {
 		assertThat(this.gemfireConfiguration.getPoolName()).isEqualTo("TestPool");
 		assertThat(this.gemfireConfiguration.getServerRegionShortcut()).isEqualTo(RegionShortcut.REPLICATE);
 		assertThat(this.gemfireConfiguration.getSessionRegionName()).isEqualTo("TEST");
+		assertThat(this.gemfireConfiguration.getSessionSerializerBeanName()).isEqualTo("testSessionSerializer");
 
-		verify(mockAnnotationMetadata, times(1)).getAnnotationAttributes(eq(EnableGemFireHttpSession.class.getName()));
+		verify(mockAnnotationMetadata, times(1))
+			.getAnnotationAttributes(eq(EnableGemFireHttpSession.class.getName()));
+
+	}
+
+	@Test
+	public void postConstructInitSetsSystemPropertyAndRegistersBeanAlias() {
+
+		ConfigurableListableBeanFactory mockBeanFactory = mock(ConfigurableListableBeanFactory.class);
+
+		ConfigurableApplicationContext mockApplicationContext = mock(ConfigurableApplicationContext.class);
+
+		given(mockApplicationContext.getBeanFactory()).willReturn(mockBeanFactory);
+
+		assertThat(System.getProperty(GemFireHttpSessionConfiguration.SESSION_SERIALIZER_REGISTERED_ALIAS)).isNull();
+
+		this.gemfireConfiguration.setApplicationContext(mockApplicationContext);
+		this.gemfireConfiguration.setSessionSerializerBeanName("testSessionSerializer");
+		this.gemfireConfiguration.init();
+
+		assertThat(this.gemfireConfiguration.getApplicationContext()).isSameAs(mockApplicationContext);
+		assertThat(System.getProperty(GemFireHttpSessionConfiguration.SESSION_SERIALIZER_QUALIFIER_PROPERTY_NAME))
+			.isEqualTo("testSessionSerializer");
+
+		verify(mockApplicationContext, times(1)).getBeanFactory();
+
+		verify(mockBeanFactory, times(1)).registerAlias(eq("testSessionSerializer"),
+			eq(GemFireHttpSessionConfiguration.SESSION_SERIALIZER_REGISTERED_ALIAS));
 	}
 
 	@Test

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/config/annotation/web/http/support/GemFireCacheTypeAwareRegionFactoryBeanTests.java

@@ -39,7 +39,7 @@ import org.springframework.data.gemfire.client.Interest;
 import org.springframework.session.Session;
 
 /**
- * The GemFireCacheTypeAwareRegionFactoryBeanTest class is a test suite of test cases
+ * The GemFireCacheTypeAwareRegionFactoryBeanTests class is a test suite of test cases
  * testing the contract and functionality of the GemFireCacheTypeAwareRegionFactoryBean
  * class.
  *
@@ -60,7 +60,7 @@ import org.springframework.session.Session;
  * @see org.apache.geode.cache.client.ClientRegionShortcut
  */
 @RunWith(MockitoJUnitRunner.class)
-public class GemFireCacheTypeAwareRegionFactoryBeanTest {
+public class GemFireCacheTypeAwareRegionFactoryBeanTests {
 
 	@Mock
 	Cache mockCache;
@@ -89,13 +89,13 @@ public class GemFireCacheTypeAwareRegionFactoryBeanTest {
 			@Override
 			protected Region<Object, Session> newClientRegion(GemFireCache gemfireCache) throws Exception {
 				assertThat(gemfireCache).isSameAs(expectedCache);
-				return GemFireCacheTypeAwareRegionFactoryBeanTest.this.mockClientRegion;
+				return GemFireCacheTypeAwareRegionFactoryBeanTests.this.mockClientRegion;
 			}
 
 			@Override
 			protected Region<Object, Session> newServerRegion(GemFireCache gemfireCache) throws Exception {
 				assertThat(gemfireCache).isSameAs(expectedCache);
-				return GemFireCacheTypeAwareRegionFactoryBeanTest.this.mockServerRegion;
+				return GemFireCacheTypeAwareRegionFactoryBeanTests.this.mockServerRegion;
 			}
 		};
 

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/serialization/data/provider/DataSerializableSessionAttributesSerializerTests.java

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.session.data.gemfire.serialization.data.provider;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.springframework.data.gemfire.util.CollectionUtils.asSet;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.util.Arrays;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.junit.Test;
+
+/**
+ * Unit tests for {@link DataSerializableSessionAttributesSerializer}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.mockito.Mock
+ * @see org.mockito.Mockito
+ * @see org.mockito.Spy
+ * @see org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes
+ * @see org.springframework.session.data.gemfire.serialization.data.provider.DataSerializableSessionAttributesSerializer
+ * @since 2.0.0
+ */
+public class DataSerializableSessionAttributesSerializerTests {
+
+	private DataSerializableSessionAttributesSerializer sessionAttributesSerializer =
+		spy(new DataSerializableSessionAttributesSerializer());
+
+	@Test
+	public void getIdReturnsSameValue() {
+
+		int id = this.sessionAttributesSerializer.getId();
+
+		assertThat(id).isNotEqualTo(0);
+		assertThat(id).isEqualTo(this.sessionAttributesSerializer.getId());
+	}
+
+	@Test
+	public void supportedClassesContainsGemFireSessionAttributes() {
+		assertThat(this.sessionAttributesSerializer.getSupportedClasses()).contains(GemFireSessionAttributes.class);
+	}
+
+	@Test
+	public void sessionAttributesToData() throws Exception {
+
+		DataOutput mockDataOutput = mock(DataOutput.class);
+
+		GemFireSessionAttributes sessionAttributes = GemFireSessionAttributes.create();
+
+		sessionAttributes.setAttribute("attrOne", "testOne");
+		sessionAttributes.setAttribute("attrTwo", "testTwo");
+
+		doAnswer(invocation -> {
+
+			DataOutput dataOutput = invocation.getArgument(1);
+
+			dataOutput.writeUTF(invocation.getArgument(0));
+
+			return null;
+
+		}).when(sessionAttributesSerializer).serializeObject(any(), any(DataOutput.class));
+
+		sessionAttributesSerializer.serialize(sessionAttributes, mockDataOutput);
+
+		verify(mockDataOutput, times(1)).writeInt(eq(2));
+		verify(mockDataOutput, times(1)).writeUTF(eq("attrOne"));
+		verify(mockDataOutput, times(1)).writeUTF(eq("testOne"));
+		verify(mockDataOutput, times(1)).writeUTF(eq("attrTwo"));
+		verify(mockDataOutput, times(1)).writeUTF(eq("testTwo"));
+	}
+
+	@Test
+	public void sessionAttributesFromData() throws Exception {
+
+		AtomicInteger count =  new AtomicInteger(0);
+
+		DataInput mockDataInput = mock(DataInput.class);
+
+		given(mockDataInput.readInt()).willReturn(2);
+		given(mockDataInput.readUTF()).willReturn("attrOne").willReturn("attrTwo");
+
+		doAnswer(invocation -> Arrays.asList("testOne", "testTwo").get(count.getAndIncrement()))
+			.when(sessionAttributesSerializer).deserializeObject(any(DataInput.class));
+
+		GemFireSessionAttributes sessionAttributes = sessionAttributesSerializer.deserialize(mockDataInput);
+
+		assertThat(sessionAttributes).isNotNull();
+		assertThat(sessionAttributes.getAttributeNames()).hasSize(2);
+		assertThat(sessionAttributes.getAttributeNames()).containsAll(asSet("attrOne", "attrTwo"));
+		assertThat(sessionAttributes.<String>getAttribute("attrOne")).isEqualTo("testOne");
+		assertThat(sessionAttributes.<String>getAttribute("attrTwo")).isEqualTo("testTwo");
+
+		verify(mockDataInput, times(1)).readInt();
+		verify(mockDataInput, times(2)).readUTF();
+	}
+}

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/serialization/data/provider/DataSerializableSessionSerializerTests.java

@@ -0,0 +1,201 @@
+/*
+ * Copyright 2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.session.data.gemfire.serialization.data.provider;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.isA;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.springframework.data.gemfire.util.CollectionUtils.asSet;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession;
+import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutput;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.time.Duration;
+import java.time.Instant;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.Test;
+
+import org.springframework.session.FindByIndexNameSessionRepository;
+
+/**
+ * Unit tests for {@link DataSerializableSessionSerializer}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.mockito.Mock
+ * @see org.mockito.Mockito
+ * @see org.mockito.Spy
+ * @see org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession
+ * @see org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSessionAttributes
+ * @see org.springframework.session.data.gemfire.serialization.data.provider.DataSerializableSessionSerializer
+ * @since 2.0.0
+ */
+public class DataSerializableSessionSerializerTests {
+
+	private DataSerializableSessionSerializer sessionSerializer = spy(new DataSerializableSessionSerializer());
+
+	@Test
+	public void getIdReturnsSameValue() {
+
+		int id = this.sessionSerializer.getId();
+
+		assertThat(id).isNotEqualTo(0);
+		assertThat(id).isEqualTo((this.sessionSerializer.getId()));
+	}
+
+	@Test
+	public void supportedClassContainsGemFireSession() {
+		assertThat(this.sessionSerializer.getSupportedClasses()).contains(GemFireSession.class);
+	}
+
+	@Test
+	public void sessionToData() throws Exception {
+
+		GemFireSession<?> session = GemFireSession.create();
+
+		session.setLastAccessedTime(Instant.ofEpochMilli(123L));
+		session.setMaxInactiveInterval(Duration.ofSeconds(60L));
+		session.setPrincipalName("jblum");
+
+		DataOutput mockDataOutput = mock(DataOutput.class);
+
+		doAnswer(invocation -> {
+			assertThat(invocation.<GemFireSessionAttributes>getArgument(0)).isEqualTo(session.getAttributes());
+			assertThat(invocation.<DataOutput>getArgument(1)).isEqualTo(mockDataOutput);
+			return null;
+		}).when(this.sessionSerializer).serializeObject(any(), any(DataOutput.class));
+
+		assertThat(session.hasDelta()).isTrue();
+
+		this.sessionSerializer.serialize(session, mockDataOutput);
+
+		assertThat(session.hasDelta()).isFalse();
+
+		verify(mockDataOutput, times(1)).writeUTF(eq(session.getId()));
+		verify(mockDataOutput, times(1)).writeLong(eq(session.getCreationTime().toEpochMilli()));
+		verify(mockDataOutput, times(1)).writeLong(eq(session.getLastAccessedTime().toEpochMilli()));
+		verify(mockDataOutput, times(1)).writeLong(eq(session.getMaxInactiveInterval().getSeconds()));
+		verify(mockDataOutput, times(1)).writeInt(eq("jblum".length()));
+		verify(mockDataOutput, times(1)).writeUTF(eq(session.getPrincipalName()));
+		verify(this.sessionSerializer, times(1))
+			.serializeObject(eq(session.getAttributes()), eq(mockDataOutput));
+	}
+
+	@Test
+	public void sessionFromData() throws Exception {
+
+		long expectedCreationTime = 1L;
+		long expectedLastAccessedTime = 2L;
+		long expectedMaxInactiveIntervalInSeconds = TimeUnit.HOURS.toSeconds(2);
+
+		String expectedPrincipalName = "jblum";
+		String expectedSessionId = "2";
+
+		DataInput mockDataInput = mock(DataInput.class);
+
+		given(mockDataInput.readUTF()).willReturn(expectedSessionId).willReturn(expectedPrincipalName);
+		given(mockDataInput.readLong()).willReturn(expectedCreationTime).willReturn(expectedLastAccessedTime)
+			.willReturn(expectedMaxInactiveIntervalInSeconds);
+		given(mockDataInput.readInt()).willReturn(expectedPrincipalName.length());
+
+		doAnswer(invocation -> {
+
+			GemFireSessionAttributes sessionAttributes = GemFireSessionAttributes.create();
+
+			sessionAttributes.setAttribute("attrOne", "testOne");
+			sessionAttributes.setAttribute("attrTwo", "testTwo");
+
+			return sessionAttributes;
+
+		}).when(this.sessionSerializer).deserializeObject(any(DataInput.class));
+
+		GemFireSession<?> session = this.sessionSerializer.deserialize(mockDataInput);
+
+		Set<String> expectedAttributeNames =
+			asSet("attrOne", "attrTwo", FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME);
+
+		assertThat(session.getId()).isEqualTo(expectedSessionId);
+		assertThat(session.getCreationTime()).isEqualTo(Instant.ofEpochMilli(expectedCreationTime));
+		assertThat(session.getLastAccessedTime()).isEqualTo(Instant.ofEpochMilli(expectedLastAccessedTime));
+		assertThat(session.getMaxInactiveInterval()).isEqualTo(Duration.ofSeconds(expectedMaxInactiveIntervalInSeconds));
+		assertThat(session.getPrincipalName()).isEqualTo(expectedPrincipalName);
+		assertThat(session.hasDelta()).isFalse();
+		assertThat(session.getAttributeNames()).hasSize(3);
+		assertThat(session.getAttributeNames()).containsAll(expectedAttributeNames);
+		assertThat(session.<String>getAttribute("attrOne")).isEqualTo("testOne");
+		assertThat(session.<String>getAttribute("attrTwo")).isEqualTo("testTwo");
+		assertThat(session.<String>getAttribute(FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME))
+			.isEqualTo(expectedPrincipalName);
+
+		verify(mockDataInput, times(2)).readUTF();
+		verify(mockDataInput, times(3)).readLong();
+		verify(mockDataInput, times(1)).readInt();
+	}
+
+	@Test
+	public void sessionToDataThenFromDataWhenPrincipalNameIsNullGetsHandledProperly()
+			throws ClassNotFoundException, IOException {
+
+		Instant beforeOrAtCreationTime = Instant.now();
+
+		GemFireSession<?> expectedSession = GemFireSession.create();
+
+		assertThat(expectedSession.getId()).isNotNull();
+		assertThat(expectedSession.getCreationTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
+		assertThat(expectedSession.getLastAccessedTime().compareTo(beforeOrAtCreationTime)).isGreaterThanOrEqualTo(0);
+		assertThat(expectedSession.getMaxInactiveInterval()).isEqualTo(Duration.ZERO);
+		assertThat(expectedSession.getPrincipalName()).isNull();
+
+		ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
+
+		doAnswer(invocation -> null).when(this.sessionSerializer).serializeObject(any(), any(DataOutput.class));
+
+		doAnswer(invocation -> GemFireSessionAttributes.create())
+			.when(this.sessionSerializer).deserializeObject(any(DataInput.class));
+
+		this.sessionSerializer.serialize(expectedSession, new DataOutputStream(outBytes));
+
+		GemFireSession<?> deserializedSession =
+			this.sessionSerializer.deserialize(new DataInputStream(new ByteArrayInputStream(outBytes.toByteArray())));
+
+		assertThat(deserializedSession).isEqualTo(expectedSession);
+		assertThat(deserializedSession.getCreationTime()).isEqualTo(expectedSession.getCreationTime());
+		assertThat(deserializedSession.getLastAccessedTime()).isEqualTo(expectedSession.getLastAccessedTime());
+		assertThat(deserializedSession.getMaxInactiveInterval()).isEqualTo(expectedSession.getMaxInactiveInterval());
+		assertThat(deserializedSession.getPrincipalName()).isNull();
+
+		verify(this.sessionSerializer, times(1))
+			.serializeObject(eq(expectedSession.getAttributes()), isA(DataOutput.class));
+
+		verify(this.sessionSerializer, times(1)).deserializeObject(isA(DataInput.class));
+	}
+}

spring-session-data-geode/src/test/java/org/springframework/session/data/gemfire/support/GemFireUtilsTests.java

@@ -47,7 +47,7 @@ import org.apache.geode.cache.client.ClientRegionShortcut;
  * @see org.mockito.Mockito
  * @see org.springframework.session.data.gemfire.support.GemFireUtils
  */
-public class GemFireUtilsTest {
+public class GemFireUtilsTests {
 
 	@Test
 	public void closeNonNullCloseableSuccessfullyReturnsTrue() throws IOException {