Update the Jetty WebSocket adapter

This changes switches from using Jetty's WebSocketListener interface
to use Jetty's @WebSocket annotations instead. The change should be
transparent but the annnotations provide a little more controler
including handling pong frames.

This change also introduces a WebSocketMessage interface.

Issue: SPR-10877

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/support/MessageHandlingException.java

@@ -28,6 +28,8 @@ import org.springframework.messaging.MessagingException;
  */
 public class MessageHandlingException extends MessagingException {
 
+	private static final long serialVersionUID = 690969923668400297L;
+
 
 	public MessageHandlingException(Message<?> message, String description, Throwable cause) {
 		super(message, description, cause);

spring-messaging/src/main/java/org/springframework/messaging/simp/BrokerAvailabilityEvent.java

@@ -26,8 +26,11 @@ import org.springframework.context.ApplicationEvent;
  */
 public class BrokerAvailabilityEvent extends ApplicationEvent {
 
+	private static final long serialVersionUID = -8156742505179181002L;
+
 	private final boolean brokerAvailable;
 
+
 	/**
 	 * Creates a new {@code BrokerAvailabilityEvent}.
 	 *

spring-websocket/src/main/java/org/springframework/web/socket/AbstractWebSocketMessage.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2002-2013 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.web.socket;
+
+import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
+
+/**
+ * A message that can be handled or sent on a WebSocket connection.
+ *
+ * @author Rossen Stoyanchev
+ * @since 4.0
+ */
+public abstract class AbstractWebSocketMessage<T> implements WebSocketMessage<T> {
+
+	private final T payload;
+
+	private final boolean last;
+
+
+	/**
+	 * Create a new WebSocket message with the given payload.
+	 *
+	 * @param payload the non-null payload
+	 */
+	AbstractWebSocketMessage(T payload) {
+		this(payload, true);
+	}
+
+	/**
+	 * Create a new WebSocket message given payload representing the full or partial
+	 * message content. When the {@code isLast} boolean flag is set to {@code false}
+	 * the message is sent as partial content and more partial messages will be
+	 * expected until the boolean flag is set to {@code true}.
+	 *
+	 * @param payload the non-null payload
+	 * @param isLast if the message is the last of a series of partial messages
+	 */
+	AbstractWebSocketMessage(T payload, boolean isLast) {
+		Assert.notNull(payload, "payload is required");
+		this.payload = payload;
+		this.last = isLast;
+	}
+
+
+	/**
+	 * Return the message payload, never be {@code null}.
+	 */
+	public T getPayload() {
+		return this.payload;
+	}
+
+	/**
+	 * Whether this is the last part of a message sent as a series of partial messages.
+	 */
+	public boolean isLast() {
+		return this.last;
+	}
+
+	@Override
+	public int hashCode() {
+		return AbstractWebSocketMessage.class.hashCode() * 13 + ObjectUtils.nullSafeHashCode(this.payload);
+	}
+
+	@Override
+	public boolean equals(Object other) {
+		if (this == other) {
+			return true;
+		}
+		if (!(other instanceof AbstractWebSocketMessage)) {
+			return false;
+		}
+		AbstractWebSocketMessage otherMessage = (AbstractWebSocketMessage) other;
+		return ObjectUtils.nullSafeEquals(this.payload, otherMessage.payload);
+	}
+
+	@Override
+	public String toString() {
+		return getClass().getSimpleName() + " payload= " + toStringPayload()
+				+ ", length=" + getPayloadSize() + ", last=" + isLast() + "]";
+	}
+
+	protected abstract String toStringPayload();
+
+	protected abstract int getPayloadSize();
+
+}

spring-websocket/src/main/java/org/springframework/web/socket/BinaryMessage.java

@@ -19,92 +19,82 @@ package org.springframework.web.socket;
 import java.nio.ByteBuffer;
 
 /**
- * A {@link WebSocketMessage} that contains a binary {@link ByteBuffer} payload.
+ * A binary WebSocket message.
  *
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public final class BinaryMessage extends WebSocketMessage<ByteBuffer> {
-
-	private byte[] bytes;
+public final class BinaryMessage extends AbstractWebSocketMessage<ByteBuffer> {
 
 
 	/**
-	 * Create a new {@link BinaryMessage} instance.
+	 * Create a new binary WebSocket message with the given ByteBuffer payload.
+	 *
 	 * @param payload the non-null payload
 	 */
 	public BinaryMessage(ByteBuffer payload) {
-		this(payload, true);
+		super(payload, true);
 	}
 
 	/**
-	 * Create a new {@link BinaryMessage} instance.
+	 * Create a new binary WebSocket message with the given payload representing the
+	 * full or partial message content. When the {@code isLast} boolean flag is set
+	 * to {@code false} the message is sent as partial content and more partial
+	 * messages will be expected until the boolean flag is set to {@code true}.
+	 *
 	 * @param payload the non-null payload
 	 * @param isLast if the message is the last of a series of partial messages
 	 */
 	public BinaryMessage(ByteBuffer payload, boolean isLast) {
 		super(payload, isLast);
-		this.bytes = null;
 	}
 
 	/**
-	 * Create a new {@link BinaryMessage} instance.
-	 * @param payload the non-null payload
+	 * Create a new binary WebSocket message with the given byte[] payload.
+	 *
+	 * @param payload a non-null payload; note that this value is not copied so care
+	 *        must be taken not to modify the array.
 	 */
 	public BinaryMessage(byte[] payload) {
-		this(payload, 0, (payload == null ? 0 : payload.length), true);
+		this(payload, true);
 	}
 
 	/**
-	 * Create a new {@link BinaryMessage} instance.
-	 * @param payload the non-null payload
+	 * Create a new binary WebSocket message with the given byte[] payload representing
+	 * the full or partial message content. When the {@code isLast} boolean flag is set
+	 * to {@code false} the message is sent as partial content and more partial
+	 * messages will be expected until the boolean flag is set to {@code true}.
+	 *
+	 * @param payload a non-null payload; note that this value is not copied so care
+	 *        must be taken not to modify the array.
 	 * @param isLast if the message is the last of a series of partial messages
 	 */
 	public BinaryMessage(byte[] payload, boolean isLast) {
-		this(payload, 0, (payload == null ? 0 : payload.length), isLast);
+		this(payload, 0, ((payload == null) ? 0 : payload.length), isLast);
 	}
 
 	/**
-	 * Create a new {@link BinaryMessage} instance by wrapping an existing byte array.
-	 * @param payload a non-null payload, NOTE: this value is not copied so care must be
-	 *        taken not to modify the array.
-	 * @param offset the offet into the array where the payload starts
-	 * @param len the length of the array considered for the payload
+	 * Create a new binary WebSocket message by wrapping an existing byte array.
+	 *
+	 * @param payload a non-null payload; note that this value is not copied so care
+	 *        must be taken not to modify the array.
+	 * @param offset the offset into the array where the payload starts
+	 * @param length the length of the array considered for the payload
 	 * @param isLast if the message is the last of a series of partial messages
 	 */
-	public BinaryMessage(byte[] payload, int offset, int len, boolean isLast) {
-		super(payload != null ? ByteBuffer.wrap(payload, offset, len) : null, isLast);
-		if(offset == 0 && len == payload.length) {
-			this.bytes = payload;
-		}
+	public BinaryMessage(byte[] payload, int offset, int length, boolean isLast) {
+		super((payload != null) ? ByteBuffer.wrap(payload, offset, length) : null, isLast);
 	}
 
 
-	/**
-	 * Returns access to the message payload as a byte array. NOTE: the returned array
-	 * should be considered read-only and should not be modified.
-	 */
-	public byte[] getByteArray() {
-		if(this.bytes == null && getPayload() != null) {
-			this.bytes = getRemainingBytes(getPayload());
-		}
-		return this.bytes;
-	}
-
-	private byte[] getRemainingBytes(ByteBuffer payload) {
-		byte[] result = new byte[getPayload().remaining()];
-		getPayload().get(result);
-		return result;
-	}
-
 	@Override
 	protected int getPayloadSize() {
-		return (getPayload() != null) ? getPayload().remaining() : 0;
+		return getPayload().remaining();
 	}
 
 	@Override
 	protected String toStringPayload() {
-		return (getPayload() != null) ? getPayload().toString() : null;
+		return getPayload().toString();
 	}
 
 }

spring-websocket/src/main/java/org/springframework/web/socket/PingMessage.java

@@ -24,21 +24,34 @@ import java.nio.ByteBuffer;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public final class PingMessage extends WebSocketMessage<ByteBuffer> {
+public final class PingMessage extends AbstractWebSocketMessage<ByteBuffer> {
 
 
+	/**
+	 * Create a new ping message with an empty payload.
+	 */
+	public PingMessage() {
+		super(ByteBuffer.allocate(0));
+	}
+
+	/**
+	 * Create a new ping message with the given ByteBuffer payload.
+	 *
+	 * @param payload the non-null payload
+	 */
 	public PingMessage(ByteBuffer payload) {
 		super(payload);
 	}
 
+
 	@Override
 	protected int getPayloadSize() {
-		return (getPayload() != null) ? getPayload().remaining() : 0;
+		return getPayload().remaining();
 	}
 
 	@Override
 	protected String toStringPayload() {
-		return (getPayload() != null) ? getPayload().toString() : null;
+		return getPayload().toString();
 	}
 
 }

spring-websocket/src/main/java/org/springframework/web/socket/PongMessage.java

@@ -24,13 +24,26 @@ import java.nio.ByteBuffer;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public final class PongMessage extends WebSocketMessage<ByteBuffer> {
+public final class PongMessage extends AbstractWebSocketMessage<ByteBuffer> {
 
 
+	/**
+	 * Create a new pong message with an empty payload.
+	 */
+	public PongMessage() {
+		super(ByteBuffer.allocate(0));
+	}
+
+	/**
+	 * Create a new pong message with the given ByteBuffer payload.
+	 *
+	 * @param payload the non-null payload
+	 */
 	public PongMessage(ByteBuffer payload) {
 		super(payload);
 	}
 
+
 	@Override
 	protected int getPayloadSize() {
 		return (getPayload() != null) ? getPayload().remaining() : 0;

spring-websocket/src/main/java/org/springframework/web/socket/ReaderTextMessage.java

@@ -1,55 +0,0 @@
-/*
- * Copyright 2002-2013 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.web.socket;
-
-/**
- * A {@link WebSocketMessage} that contains a textual {@link String} payload.
- *
- * @author Rossen Stoyanchev
- * @since 4.0
- */
-public final class ReaderTextMessage extends WebSocketMessage<String> {
-
-	/**
-	 * Create a new {@link ReaderTextMessage} instance.
-	 * @param payload the non-null payload
-	 */
-	public ReaderTextMessage(CharSequence payload) {
-		super(payload.toString(), true);
-	}
-
-	/**
-	 * Create a new {@link ReaderTextMessage} instance.
-	 * @param payload the non-null payload
-	 * @param isLast whether this the last part of a message received or transmitted in parts
-	 */
-	public ReaderTextMessage(CharSequence payload, boolean isLast) {
-		super(payload.toString(), isLast);
-	}
-
-
-	@Override
-	protected int getPayloadSize() {
-		return getPayload().length();
-	}
-
-	@Override
-	protected String toStringPayload() {
-		return (getPayloadSize() > 10) ? getPayload().substring(0, 10) + ".." : getPayload();
-	}
-
-}

spring-websocket/src/main/java/org/springframework/web/socket/TextMessage.java

@@ -17,15 +17,17 @@
 package org.springframework.web.socket;
 
 /**
- * A {@link WebSocketMessage} that contains a textual {@link String} payload.
+ * A text WebSocket message.
  *
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public final class TextMessage extends WebSocketMessage<String> {
+public final class TextMessage extends AbstractWebSocketMessage<String> {
+
 
 	/**
-	 * Create a new {@link TextMessage} instance.
+	 * Create a new text WebSocket message from the given CharSequence payload.
+	 *
 	 * @param payload the non-null payload
 	 */
 	public TextMessage(CharSequence payload) {
@@ -33,9 +35,13 @@ public final class TextMessage extends WebSocketMessage<String> {
 	}
 
 	/**
-	 * Create a new {@link TextMessage} instance.
+	 * Create a new text WebSocket message with the given payload representing the
+	 * full or partial message content. When the {@code isLast} boolean flag is set
+	 * to {@code false} the message is sent as partial content and more partial
+	 * messages will be expected until the boolean flag is set to {@code true}.
+	 *
 	 * @param payload the non-null payload
-	 * @param isLast whether this the last part of a message received or transmitted in parts
+	 * @param isLast whether this the last part of a series of partial messages
 	 */
 	public TextMessage(CharSequence payload, boolean isLast) {
 		super(payload.toString(), isLast);

spring-websocket/src/main/java/org/springframework/web/socket/WebSocketHandler.java

@@ -18,8 +18,8 @@ package org.springframework.web.socket;
 
 /**
  * A handler for WebSocket messages and lifecycle events.
- *
- * <p>Implementations of this interface are encouraged to handle exceptions locally where
+ * <p>
+ * Implementations of this interface are encouraged to handle exceptions locally where
  * it makes sense or alternatively let the exception bubble up in which case by default
  * the exception is logged and the session closed with
  * {@link CloseStatus#SERVER_ERROR SERVER_ERROR(1011)}. The exception handling
@@ -68,7 +68,13 @@ public interface WebSocketHandler {
 	void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception;
 
 	/**
-	 * Whether the WebSocketHandler handles messages in parts.
+	 * Whether the WebSocketHandler handles partial messages. If this flag is set to
+	 * {@code true} and the underlying WebSocket server supports partial messages,
+	 * then a large WebSocket message, or one of an unknown size may be split and
+	 * maybe received over multiple calls to
+	 * {@link #handleMessage(WebSocketSession, WebSocketMessage)}. The flag
+	 * {@link org.springframework.web.socket.WebSocketMessage#isLast()} indicates if
+	 * the message is partial and whether it is the last part.
 	 */
 	boolean supportsPartialMessages();
 

spring-websocket/src/main/java/org/springframework/web/socket/WebSocketMessage.java

@@ -25,72 +25,20 @@ import org.springframework.util.ObjectUtils;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public abstract class WebSocketMessage<T> {
-
-	private final T payload;
-
-	private final boolean last;
-
-
-	/**
-	 * Create a new {@link WebSocketMessage} instance with the given payload.
-	 */
-	WebSocketMessage(T payload) {
-		this(payload, true);
-	}
-
-	/**
-	 * Create a new {@link WebSocketMessage} instance with the given payload.
-	 * @param payload a non-null payload
-	 */
-	WebSocketMessage(T payload, boolean isLast) {
-		Assert.notNull(payload, "payload is required");
-		this.payload = payload;
-		this.last = isLast;
-	}
-
+public interface WebSocketMessage<T> {
 
 	/**
 	 * Returns the message payload. This will never be {@code null}.
 	 */
-	public T getPayload() {
-		return this.payload;
-	}
+	T getPayload();
 
 	/**
-	 * Whether this is the last part of a message, when partial message support on a
-	 * {@link WebSocketHandler} is enabled. If partial message support is not enabled the
-	 * returned value is always {@code true}.
+	 * When partial message support is available and requested via
+	 * {@link org.springframework.web.socket.WebSocketHandler#supportsPartialMessages()},
+	 * this method returns {@literal true} if the current message is the last part of
+	 * the complete WebSocket message sent by the client. Otherwise {@literal false}
+	 * is returned if partial message support is either not available or not enabled.
 	 */
-	public boolean isLast() {
-		return this.last;
-	}
-
-	@Override
-	public int hashCode() {
-		return WebSocketMessage.class.hashCode() * 13 + ObjectUtils.nullSafeHashCode(this.payload);
-	}
-
-	@Override
-	public boolean equals(Object other) {
-		if (this == other) {
-			return true;
-		}
-		if (!(other instanceof WebSocketMessage)) {
-			return false;
-		}
-		WebSocketMessage otherMessage = (WebSocketMessage) other;
-		return ObjectUtils.nullSafeEquals(this.payload, otherMessage.payload);
-	}
-
-	@Override
-	public String toString() {
-		return getClass().getSimpleName() + " payload= " + toStringPayload()
-				+ ", length=" + getPayloadSize() + ", last=" + isLast() + "]";
-	}
-
-	protected abstract String toStringPayload();
-
-	protected abstract int getPayloadSize();
+	boolean isLast();
 
 }

spring-websocket/src/main/java/org/springframework/web/socket/adapter/AbstractWebSocketSesssion.java

@@ -32,8 +32,6 @@ import org.springframework.web.socket.WebSocketSession;
 /**
  * An abstract base class for implementations of {@link WebSocketSession}.
  *
- * @param T the type of the native (or delegate) WebSocket session
- *
  * @author Rossen Stoyanchev
  * @since 4.0
  */

spring-websocket/src/main/java/org/springframework/web/socket/adapter/JettyWebSocketHandlerAdapter.java

@@ -19,22 +19,32 @@ package org.springframework.web.socket.adapter;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.eclipse.jetty.websocket.api.Session;
-import org.eclipse.jetty.websocket.api.WebSocketListener;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketClose;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketConnect;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketError;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketFrame;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
+import org.eclipse.jetty.websocket.api.annotations.WebSocket;
+import org.eclipse.jetty.websocket.api.extensions.Frame;
+import org.eclipse.jetty.websocket.common.OpCode;
 import org.springframework.util.Assert;
 import org.springframework.web.socket.BinaryMessage;
 import org.springframework.web.socket.CloseStatus;
+import org.springframework.web.socket.PongMessage;
 import org.springframework.web.socket.TextMessage;
 import org.springframework.web.socket.WebSocketHandler;
 import org.springframework.web.socket.support.ExceptionWebSocketHandlerDecorator;
 
+import java.nio.ByteBuffer;
+
 /**
  * Adapts {@link WebSocketHandler} to the Jetty 9 WebSocket API.
  *
- * @author Phillip Webb
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public class JettyWebSocketHandlerAdapter implements WebSocketListener {
+@WebSocket
+public class JettyWebSocketHandlerAdapter {
 
 	private static final Log logger = LogFactory.getLog(JettyWebSocketHandlerAdapter.class);
 
@@ -44,14 +54,16 @@ public class JettyWebSocketHandlerAdapter implements WebSocketListener {
 
 
 	public JettyWebSocketHandlerAdapter(WebSocketHandler webSocketHandler, JettyWebSocketSession wsSession) {
+
 		Assert.notNull(webSocketHandler, "webSocketHandler must not be null");
 		Assert.notNull(wsSession, "wsSession must not be null");
+
 		this.webSocketHandler = webSocketHandler;
 		this.wsSession = wsSession;
 	}
 
 
-	@Override
+	@OnWebSocketConnect
 	public void onWebSocketConnect(Session session) {
 		try {
 			this.wsSession.initializeNativeSession(session);
@@ -62,7 +74,7 @@ public class JettyWebSocketHandlerAdapter implements WebSocketListener {
 		}
 	}
 
-	@Override
+	@OnWebSocketMessage
 	public void onWebSocketText(String payload) {
 		TextMessage message = new TextMessage(payload);
 		try {
@@ -73,9 +85,9 @@ public class JettyWebSocketHandlerAdapter implements WebSocketListener {
 		}
 	}
 
-	@Override
-	public void onWebSocketBinary(byte[] payload, int offset, int len) {
-		BinaryMessage message = new BinaryMessage(payload, offset, len, true);
+	@OnWebSocketMessage
+	public void onWebSocketBinary(byte[] payload, int offset, int length) {
+		BinaryMessage message = new BinaryMessage(payload, offset, length, true);
 		try {
 			this.webSocketHandler.handleMessage(this.wsSession, message);
 		}
@@ -84,7 +96,20 @@ public class JettyWebSocketHandlerAdapter implements WebSocketListener {
 		}
 	}
 
-	@Override
+	@OnWebSocketFrame
+	public void onWebSocketFrame(Frame frame) {
+		if (OpCode.PONG == frame.getOpCode()) {
+			PongMessage message = new PongMessage(frame.getPayload());
+			try {
+				this.webSocketHandler.handleMessage(this.wsSession, message);
+			}
+			catch (Throwable t) {
+				ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
+			}
+		}
+	}
+
+	@OnWebSocketClose
 	public void onWebSocketClose(int statusCode, String reason) {
 		CloseStatus closeStatus = new CloseStatus(statusCode, reason);
 		try {
@@ -95,7 +120,7 @@ public class JettyWebSocketHandlerAdapter implements WebSocketListener {
 		}
 	}
 
-	@Override
+	@OnWebSocketError
 	public void onWebSocketError(Throwable cause) {
 		try {
 			this.webSocketHandler.handleTransportError(this.wsSession, cause);

spring-websocket/src/main/java/org/springframework/web/socket/support/WebSocketHttpHeaders.java

@@ -35,6 +35,8 @@ import org.springframework.util.CollectionUtils;
  */
 public class WebSocketHttpHeaders extends HttpHeaders {
 
+	private static final long serialVersionUID = -6644521016187828916L;
+
 	public static final String SEC_WEBSOCKET_ACCEPT = "Sec-WebSocket-Accept";
 
 	public static final String SEC_WEBSOCKET_EXTENSIONS = "Sec-WebSocket-Extensions";

spring-websocket/src/test/java/org/springframework/web/socket/server/config/WebSocketConfigurationTests.java

@@ -69,7 +69,7 @@ public class WebSocketConfigurationTests extends AbstractWebSocketIntegrationTes
 				new WebSocketHandlerAdapter(), getWsBaseUrl() + "/ws").get();
 
 		TestWebSocketHandler serverHandler = this.wac.getBean(TestWebSocketHandler.class);
-		assertTrue(serverHandler.latch.await(2, TimeUnit.SECONDS));
+		assertTrue(serverHandler.connectLatch.await(2, TimeUnit.SECONDS));
 
 		session.close();
 	}
@@ -81,7 +81,7 @@ public class WebSocketConfigurationTests extends AbstractWebSocketIntegrationTes
 				new WebSocketHandlerAdapter(), getWsBaseUrl() + "/sockjs/websocket").get();
 
 		TestWebSocketHandler serverHandler = this.wac.getBean(TestWebSocketHandler.class);
-		assertTrue(serverHandler.latch.await(2, TimeUnit.SECONDS));
+		assertTrue(serverHandler.connectLatch.await(2, TimeUnit.SECONDS));
 
 		session.close();
 	}
@@ -113,11 +113,11 @@ public class WebSocketConfigurationTests extends AbstractWebSocketIntegrationTes
 
 	private static class TestWebSocketHandler extends WebSocketHandlerAdapter {
 
-		private CountDownLatch latch = new CountDownLatch(1);
+		private CountDownLatch connectLatch = new CountDownLatch(1);
 
 		@Override
 		public void afterConnectionEstablished(WebSocketSession session) throws Exception {
-			this.latch.countDown();
+			this.connectLatch.countDown();
 		}
 	}