Issue #4747 - filter out synthetic annotated methods

Signed-off-by: Lachlan Roberts <lachlan@webtide.com>

jetty-websocket/websocket-javax-tests/src/test/java/org/eclipse/jetty/websocket/javax/tests/SyntheticOnMessageTest.java

@@ -0,0 +1,112 @@
+//
+// ========================================================================
+// Copyright (c) 1995-2020 Mort Bay Consulting Pty Ltd and others.
+//
+// This program and the accompanying materials are made available under
+// the terms of the Eclipse Public License 2.0 which is available at
+// https://www.eclipse.org/legal/epl-2.0
+//
+// This Source Code may also be made available under the following
+// Secondary Licenses when the conditions for such availability set
+// forth in the Eclipse Public License, v. 2.0 are satisfied:
+// the Apache License v2.0 which is available at
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+// ========================================================================
+//
+
+package org.eclipse.jetty.websocket.javax.tests;
+
+import java.lang.reflect.Method;
+import java.net.URI;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+import javax.websocket.CloseReason;
+import javax.websocket.ContainerProvider;
+import javax.websocket.OnMessage;
+import javax.websocket.Session;
+import javax.websocket.WebSocketContainer;
+import javax.websocket.server.ServerEndpoint;
+
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.server.ServerConnector;
+import org.eclipse.jetty.servlet.ServletContextHandler;
+import org.eclipse.jetty.util.component.LifeCycle;
+import org.eclipse.jetty.websocket.javax.server.config.JavaxWebSocketServletContainerInitializer;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class SyntheticOnMessageTest
+{
+    private Server server;
+    private URI serverUri;
+    private ServerConnector connector;
+    private WebSocketContainer client;
+
+    @BeforeEach
+    public void before() throws Exception
+    {
+        server = new Server();
+        connector = new ServerConnector(server);
+        server.addConnector(connector);
+
+        ServletContextHandler contextHandler = new ServletContextHandler();
+        contextHandler.setContextPath("/");
+        JavaxWebSocketServletContainerInitializer.configure(contextHandler, (context, container) ->
+            container.addEndpoint(ServerSocket.class));
+        server.setHandler(contextHandler);
+        server.start();
+        serverUri = URI.create("ws://localhost:" + connector.getLocalPort());
+        client = ContainerProvider.getWebSocketContainer();
+    }
+
+    @AfterEach
+    public void after() throws Exception
+    {
+        LifeCycle.stop(client);
+        server.stop();
+    }
+
+    public static class AnnotatedEndpoint<T>
+    {
+        public void onMessage(T message)
+        {
+        }
+    }
+
+    @ServerEndpoint("/")
+    public static class ServerSocket extends AnnotatedEndpoint<String>
+    {
+        @OnMessage
+        public void onMessage(String message)
+        {
+        }
+    }
+
+    @Test
+    public void syntheticOnMessageTest() throws Exception
+    {
+        // ServerSocket has two annotated onMessage methods, one is a synthetic bridge method generated
+        // by the compiler and shouldn't be used.
+        List<Method> annotatedOnMessages = Stream.of(ServerSocket.class.getDeclaredMethods())
+            .filter(method -> method.getAnnotation(OnMessage.class) != null)
+            .collect(Collectors.toList());
+        assertThat(annotatedOnMessages.size(), is(2));
+
+        // We should correctly filter out all synthetic methods so we should not get an InvalidSignatureException.
+        EventSocket clientSocket = new EventSocket();
+        Session session = client.connectToServer(clientSocket, serverUri);
+        assertTrue(clientSocket.openLatch.await(5, TimeUnit.SECONDS));
+        session.close();
+        assertTrue(clientSocket.closeLatch.await(5, TimeUnit.SECONDS));
+        assertThat(clientSocket.closeReason.getCloseCode(), is(CloseReason.CloseCodes.NORMAL_CLOSURE));
+    }
+}

jetty-websocket/websocket-util/src/main/java/org/eclipse/jetty/websocket/util/ReflectUtils.java

@@ -29,6 +29,7 @@ import java.lang.reflect.TypeVariable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.regex.Pattern;
+import java.util.stream.Stream;
 
 public class ReflectUtils
 {
@@ -220,27 +221,19 @@ public class ReflectUtils
 
     public static Method[] findAnnotatedMethods(Class<?> pojo, Class<? extends Annotation> anno)
     {
-        List<Method> methods = null;
         Class<?> clazz = pojo;
-
+        List<Method> methods = new ArrayList<>();
         while ((clazz != null) && Object.class.isAssignableFrom(clazz))
         {
-            for (Method method : clazz.getDeclaredMethods())
-            {
-                if (method.getAnnotation(anno) != null)
-                {
-                    if (methods == null)
-                        methods = new ArrayList<>();
-                    methods.add(method);
-                }
-            }
+            Stream.of(clazz.getDeclaredMethods())
+                .filter(method -> !method.isSynthetic() && (method.getAnnotation(anno) != null))
+                .forEach(methods::add);
             clazz = clazz.getSuperclass();
         }
 
-        if (methods == null)
+        if (methods.isEmpty())
             return null;
-        int len = methods.size();
-        return methods.toArray(new Method[len]);
+        return methods.toArray(new Method[0]);
     }
 
     /**