Revised Jetty 9.3 vs 9.4 differentiation

Issue: SPR-14940
(cherry picked from commit 52799c0)

Author: jhoeller

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

@@ -42,15 +42,13 @@ public abstract class AbstractWebSocketSession<T> implements NativeWebSocketSess
 
 	protected static final Log logger = LogFactory.getLog(NativeWebSocketSession.class);
 
+	private final Map<String, Object> attributes = new ConcurrentHashMap<String, Object>();
 
 	private T nativeSession;
 
-	private final Map<String, Object> attributes = new ConcurrentHashMap<String, Object>();
-
 
 	/**
 	 * Create a new instance and associate the given attributes with it.
-	 *
 	 * @param attributes attributes from the HTTP handshake to associate with the WebSocket
 	 * session; the provided attributes are copied, the original map is not used.
 	 */
@@ -83,7 +81,7 @@ public <R> R getNativeSession(Class<R> requiredType) {
 	}
 
 	public void initializeNativeSession(T session) {
-		Assert.notNull(session, "session must not be null");
+		Assert.notNull(session, "WebSocket session must not be null");
 		this.nativeSession = session;
 	}
 
@@ -125,6 +123,7 @@ else if (message instanceof PongMessage) {
 
 	protected abstract void sendPongMessage(PongMessage message) throws IOException;
 
+
 	@Override
 	public final void close() throws IOException {
 		close(CloseStatus.NORMAL);

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

@@ -45,59 +45,61 @@
 import org.springframework.web.socket.adapter.AbstractWebSocketSession;
 
 /**
- * A {@link WebSocketSession} for use with the Jetty 9 WebSocket API.
+ * A {@link WebSocketSession} for use with the Jetty 9.3/9.4 WebSocket API.
  *
  * @author Phillip Webb
  * @author Rossen Stoyanchev
  * @author Brian Clozel
+ * @author Juergen Hoeller
  * @since 4.0
  */
 public class JettyWebSocketSession extends AbstractWebSocketSession<Session> {
 
 	// As of Jetty 9.4, UpgradeRequest and UpgradeResponse are interfaces instead of classes
-	private static final boolean isJetty94;
+	private static final boolean directInterfaceCalls;
 
 	private static Method getUpgradeRequest;
 	private static Method getUpgradeResponse;
 	private static Method getRequestURI;
 	private static Method getHeaders;
+	private static Method getUserPrincipal;
 	private static Method getAcceptedSubProtocol;
 	private static Method getExtensions;
-	private static Method getUserPrincipal;
-
-	private String id;
-
-	private URI uri;
-
-	private HttpHeaders headers;
-
-	private String acceptedProtocol;
-
-	private List<WebSocketExtension> extensions;
-
-	private Principal user;
 
 	static {
-		isJetty94 = UpgradeRequest.class.isInterface();
-		if (!isJetty94) {
+		directInterfaceCalls = UpgradeRequest.class.isInterface();
+		if (!directInterfaceCalls) {
 			try {
 				getUpgradeRequest = Session.class.getMethod("getUpgradeRequest");
 				getUpgradeResponse = Session.class.getMethod("getUpgradeResponse");
 				getRequestURI = UpgradeRequest.class.getMethod("getRequestURI");
 				getHeaders = UpgradeRequest.class.getMethod("getHeaders");
+				getUserPrincipal = UpgradeRequest.class.getMethod("getUserPrincipal");
 				getAcceptedSubProtocol = UpgradeResponse.class.getMethod("getAcceptedSubProtocol");
 				getExtensions = UpgradeResponse.class.getMethod("getExtensions");
-				getUserPrincipal = UpgradeRequest.class.getMethod("getUserPrincipal");
 			}
 			catch (NoSuchMethodException ex) {
 				throw new IllegalStateException("Incompatible Jetty API", ex);
 			}
 		}
 	}
 
+
+	private String id;
+
+	private URI uri;
+
+	private HttpHeaders headers;
+
+	private String acceptedProtocol;
+
+	private List<WebSocketExtension> extensions;
+
+	private Principal user;
+
+
 	/**
 	 * Create a new {@link JettyWebSocketSession} instance.
-	 *
 	 * @param attributes attributes from the HTTP handshake to associate with the WebSocket session
 	 */
 	public JettyWebSocketSession(Map<String, Object> attributes) {
@@ -106,11 +108,10 @@ public JettyWebSocketSession(Map<String, Object> attributes) {
 
 	/**
 	 * Create a new {@link JettyWebSocketSession} instance associated with the given user.
-	 *
 	 * @param attributes attributes from the HTTP handshake to associate with the WebSocket
 	 * session; the provided attributes are copied, the original map is not used.
-	 * @param user the user associated with the session; if {@code null} we'll fallback on the user
-	 *  available via {@link org.eclipse.jetty.websocket.api.Session#getUpgradeRequest()}
+	 * @param user the user associated with the session; if {@code null} we'll fallback on the
+	 * user available via {@link org.eclipse.jetty.websocket.api.Session#getUpgradeRequest()}
 	 */
 	public JettyWebSocketSession(Map<String, Object> attributes, Principal user) {
 		super(attributes);
@@ -191,36 +192,32 @@ public int getBinaryMessageSizeLimit() {
 
 	@Override
 	public boolean isOpen() {
-		return ((getNativeSession() != null) && getNativeSession().isOpen());
+		return (getNativeSession() != null && getNativeSession().isOpen());
 	}
 
+
 	@Override
 	public void initializeNativeSession(Session session) {
 		super.initializeNativeSession(session);
-		if (isJetty94) {
-			initializeJetty94Session(session);
+		if (directInterfaceCalls) {
+			initializeJettySessionDirectly(session);
 		}
 		else {
-			initializeJettySession(session);
+			initializeJettySessionReflectively(session);
 		}
 	}
 
-	@SuppressWarnings("unchecked")
-	private void initializeJettySession(Session session) {
-
-		Object request = ReflectionUtils.invokeMethod(getUpgradeRequest, session);
-		Object response = ReflectionUtils.invokeMethod(getUpgradeResponse, session);
-
+	private void initializeJettySessionDirectly(Session session) {
 		this.id = ObjectUtils.getIdentityHexString(getNativeSession());
-		this.uri = (URI) ReflectionUtils.invokeMethod(getRequestURI, request);
+		this.uri = session.getUpgradeRequest().getRequestURI();
 
 		this.headers = new HttpHeaders();
-		this.headers.putAll((Map<String, List<String>>) ReflectionUtils.invokeMethod(getHeaders, request));
+		this.headers.putAll(session.getUpgradeRequest().getHeaders());
 		this.headers = HttpHeaders.readOnlyHttpHeaders(headers);
 
-		this.acceptedProtocol = (String) ReflectionUtils.invokeMethod(getAcceptedSubProtocol, response);
+		this.acceptedProtocol = session.getUpgradeResponse().getAcceptedSubProtocol();
 
-		List<ExtensionConfig> source = (List<ExtensionConfig>) ReflectionUtils.invokeMethod(getExtensions, response);
+		List<ExtensionConfig> source = session.getUpgradeResponse().getExtensions();
 		if (source != null) {
 			this.extensions = new ArrayList<WebSocketExtension>(source.size());
 			for (ExtensionConfig ec : source) {
@@ -232,36 +229,41 @@ private void initializeJettySession(Session session) {
 		}
 
 		if (this.user == null) {
-			this.user = (Principal) ReflectionUtils.invokeMethod(getUserPrincipal, request);
+			this.user = session.getUpgradeRequest().getUserPrincipal();
 		}
 	}
 
-	private void initializeJetty94Session(Session session) {
+	@SuppressWarnings("unchecked")
+	private void initializeJettySessionReflectively(Session session) {
+		Object request = ReflectionUtils.invokeMethod(getUpgradeRequest, session);
+		Object response = ReflectionUtils.invokeMethod(getUpgradeResponse, session);
+
 		this.id = ObjectUtils.getIdentityHexString(getNativeSession());
-		this.uri = session.getUpgradeRequest().getRequestURI();
+		this.uri = (URI) ReflectionUtils.invokeMethod(getRequestURI, request);
 
 		this.headers = new HttpHeaders();
-		this.headers.putAll(session.getUpgradeRequest().getHeaders());
+		this.headers.putAll((Map<String, List<String>>) ReflectionUtils.invokeMethod(getHeaders, request));
 		this.headers = HttpHeaders.readOnlyHttpHeaders(headers);
 
-		this.acceptedProtocol = session.getUpgradeResponse().getAcceptedSubProtocol();
+		this.acceptedProtocol = (String) ReflectionUtils.invokeMethod(getAcceptedSubProtocol, response);
 
-		List<ExtensionConfig> source = getNativeSession().getUpgradeResponse().getExtensions();
+		List<ExtensionConfig> source = (List<ExtensionConfig>) ReflectionUtils.invokeMethod(getExtensions, response);
 		if (source != null) {
 			this.extensions = new ArrayList<WebSocketExtension>(source.size());
 			for (ExtensionConfig ec : source) {
 				this.extensions.add(new WebSocketExtension(ec.getName(), ec.getParameters()));
 			}
 		}
 		else {
-				this.extensions = new ArrayList<WebSocketExtension>(0);
+			this.extensions = new ArrayList<WebSocketExtension>(0);
 		}
 
 		if (this.user == null) {
-			this.user = session.getUpgradeRequest().getUserPrincipal();
+			this.user = (Principal) ReflectionUtils.invokeMethod(getUserPrincipal, request);
 		}
 	}
 
+
 	@Override
 	protected void sendTextMessage(TextMessage message) throws IOException {
 		getRemoteEndpoint().sendString(message.getPayload());
@@ -287,7 +289,7 @@ private RemoteEndpoint getRemoteEndpoint() throws IOException {
 			return getNativeSession().getRemote();
 		}
 		catch (WebSocketException ex) {
-			throw new IOException("Unable to obtain RemoteEndpoint in session=" + getId(), ex);
+			throw new IOException("Unable to obtain RemoteEndpoint in session " + getId(), ex);
 		}
 	}