Add SockJsMessageCodec

A SockJS message frame is an array of JSON-encoded messages and before
this change the use of the Jackson 2 library was hard-coded.

A Jackson 2 and Jackson 1.x implementations are provided and
automatically used if those libraries are present on the classpath.

Issue: SPR-10800

spring-websocket/src/test/java/org/springframework/web/socket/sockjs/AbstractSockJsServiceTests.java

@@ -224,6 +224,11 @@ public class AbstractSockJsServiceTests extends AbstractHttpRequestTests {
 			super(scheduler);
 		}
 
+		@Override
+		public SockJsMessageCodec getMessageCodecRequired() {
+			throw new UnsupportedOperationException();
+		}
+
 		@Override
 		protected void handleRawWebSocketRequest(ServerHttpRequest request,
 				ServerHttpResponse response, WebSocketHandler handler) throws IOException {

spring-websocket/src/test/java/org/springframework/web/socket/sockjs/StubSockJsConfig.java

@@ -18,6 +18,7 @@ package org.springframework.web.socket.sockjs;
 
 import org.springframework.scheduling.TaskScheduler;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
+import org.springframework.web.socket.sockjs.support.Jackson2SockJsMessageCodec;
 
 /**
  * @author Rossen Stoyanchev
@@ -30,6 +31,8 @@ public class StubSockJsConfig implements SockJsConfiguration {
 
 	private TaskScheduler taskScheduler = new ThreadPoolTaskScheduler();
 
+	private SockJsMessageCodec messageCodec = new Jackson2SockJsMessageCodec();
+
 
 	@Override
 	public int getStreamBytesLimit() {
@@ -58,4 +61,17 @@ public class StubSockJsConfig implements SockJsConfiguration {
 		this.taskScheduler = taskScheduler;
 	}
 
+	@Override
+	public SockJsMessageCodec getMessageCodecRequired() {
+		return this.messageCodec;
+	}
+
+	public SockJsMessageCodec getMessageCodec() {
+		return messageCodec;
+	}
+
+	public void setMessageCodec(SockJsMessageCodec messageCodec) {
+		this.messageCodec = messageCodec;
+	}
+
 }

spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/DefaultSockJsServiceTests.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.web.socket.sockjs.support;
+package org.springframework.web.socket.sockjs.transport;
 
 import java.util.Collections;
 import java.util.HashSet;
@@ -30,6 +30,7 @@ import org.springframework.scheduling.TaskScheduler;
 import org.springframework.web.socket.AbstractHttpRequestTests;
 import org.springframework.web.socket.WebSocketHandler;
 import org.springframework.web.socket.sockjs.AbstractSockJsSession;
+import org.springframework.web.socket.sockjs.SockJsConfiguration;
 import org.springframework.web.socket.sockjs.SockJsSessionFactory;
 import org.springframework.web.socket.sockjs.StubSockJsConfig;
 import org.springframework.web.socket.sockjs.TestSockJsSession;
@@ -164,6 +165,10 @@ public class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 			return TransportType.XHR;
 		}
 
+		@Override
+		public void setSockJsConfiguration(SockJsConfiguration sockJsConfig) {
+		}
+
 		@Override
 		public void handleRequest(ServerHttpRequest request, ServerHttpResponse response,
 				WebSocketHandler handler, AbstractSockJsSession session) throws TransportErrorException {
@@ -176,6 +181,7 @@ public class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 		public AbstractSockJsSession createSession(String sessionId, WebSocketHandler webSocketHandler) {
 			return new TestSockJsSession(sessionId, new StubSockJsConfig(), webSocketHandler);
 		}
+
 	}
 
 	private static class StubXhrSendTransportHandler implements TransportHandler {
@@ -185,6 +191,10 @@ public class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 			return TransportType.XHR_SEND;
 		}
 
+		@Override
+		public void setSockJsConfiguration(SockJsConfiguration sockJsConfig) {
+		}
+
 		@Override
 		public void handleRequest(ServerHttpRequest request, ServerHttpResponse response,
 				WebSocketHandler handler, AbstractSockJsSession session) throws TransportErrorException {

spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/HttpReceivingTransportHandlerTests.java

@@ -105,16 +105,20 @@ public class HttpReceivingTransportHandlerTests  extends AbstractHttpRequestTest
 	@Test
 	public void delegateMessageException() throws Exception {
 
+		StubSockJsConfig sockJsConfig = new StubSockJsConfig();
+
 		this.servletRequest.setContent("[\"x\"]".getBytes("UTF-8"));
 
 		WebSocketHandler webSocketHandler = mock(WebSocketHandler.class);
-		TestSockJsSession session = new TestSockJsSession("1", new StubSockJsConfig(), webSocketHandler);
+		TestSockJsSession session = new TestSockJsSession("1", sockJsConfig, webSocketHandler);
 		session.delegateConnectionEstablished();
 
 		doThrow(new Exception()).when(webSocketHandler).handleMessage(session, new TextMessage("x"));
 
 		try {
-			new XhrTransportHandler().handleRequest(this.request, this.response, webSocketHandler, session);
+			XhrTransportHandler transportHandler = new XhrTransportHandler();
+			transportHandler.setSockJsConfiguration(sockJsConfig);
+			transportHandler.handleRequest(this.request, this.response, webSocketHandler, session);
 			fail("Expected exception");
 		}
 		catch (TransportErrorException ex) {
@@ -129,6 +133,7 @@ public class HttpReceivingTransportHandlerTests  extends AbstractHttpRequestTest
 		WebSocketHandler webSocketHandler = mock(WebSocketHandler.class);
 		AbstractSockJsSession session = new TestSockJsSession("1", new StubSockJsConfig(), webSocketHandler);
 
+		transportHandler.setSockJsConfiguration(new StubSockJsConfig());
 		transportHandler.handleRequest(this.request, this.response, webSocketHandler, session);
 
 		assertEquals("text/plain;charset=UTF-8", this.response.getHeaders().getContentType().toString());