UndertowRequestUpgradeStrategy auto-adapts to Undertow 1.3's different Pool API

Issue: SPR-13494

Author: jhoeller

spring-websocket/src/main/java/org/springframework/web/socket/server/standard/UndertowRequestUpgradeStrategy.java

@@ -17,6 +17,7 @@
 package org.springframework.web.socket.server.standard;
 
 import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -48,57 +49,84 @@
 import io.undertow.websockets.jsr.handshake.JsrHybi07Handshake;
 import io.undertow.websockets.jsr.handshake.JsrHybi08Handshake;
 import io.undertow.websockets.jsr.handshake.JsrHybi13Handshake;
+import io.undertow.websockets.spi.WebSocketHttpExchange;
 import org.xnio.StreamConnection;
 
 import org.springframework.http.server.ServerHttpRequest;
 import org.springframework.http.server.ServerHttpResponse;
 import org.springframework.util.ClassUtils;
+import org.springframework.util.ReflectionUtils;
 import org.springframework.web.socket.server.HandshakeFailureException;
 
 /**
  * A {@link org.springframework.web.socket.server.RequestUpgradeStrategy} for use
  * with WildFly and its underlying Undertow web server.
  *
- * <p>Compatible with Undertow 1.0, 1.1, 1.2 - as included in WildFly 8.x and 9.0.
+ * <p>Compatible with Undertow 1.0 to 1.3 - as included in WildFly 8.x, 9 and 10.
  *
  * @author Rossen Stoyanchev
+ * @author Brian Clozel
+ * @author Juergen Hoeller
  * @since 4.0.1
  */
 public class UndertowRequestUpgradeStrategy extends AbstractStandardUpgradeStrategy {
 
 	private static final Constructor<ServletWebSocketHttpExchange> exchangeConstructor;
 
+	private static final boolean exchangeConstructorWithPeerConnections;
+
 	private static final Constructor<ConfiguredServerEndpoint> endpointConstructor;
 
-	private static final boolean undertow10Present;
+	private static final boolean endpointConstructorWithEndpointFactory;
+
+	private static final Method getBufferPoolMethod;
 
-	private static final boolean undertow11Present;
+	private static final Method createChannelMethod;
 
 	static {
-		Class<ServletWebSocketHttpExchange> exchangeType = ServletWebSocketHttpExchange.class;
-		Class<?>[] exchangeParamTypes = new Class<?>[] {HttpServletRequest.class, HttpServletResponse.class, Set.class};
-		if (ClassUtils.hasConstructor(exchangeType, exchangeParamTypes)) {
-			exchangeConstructor = ClassUtils.getConstructorIfAvailable(exchangeType, exchangeParamTypes);
-			undertow10Present = false;
-		}
-		else {
-			exchangeParamTypes = new Class<?>[] {HttpServletRequest.class, HttpServletResponse.class};
-			exchangeConstructor = ClassUtils.getConstructorIfAvailable(exchangeType, exchangeParamTypes);
-			undertow10Present = true;
-		}
+		try {
+			Class<ServletWebSocketHttpExchange> exchangeType = ServletWebSocketHttpExchange.class;
+			Class<?>[] exchangeParamTypes =
+					new Class<?>[] {HttpServletRequest.class, HttpServletResponse.class, Set.class};
+			Constructor<ServletWebSocketHttpExchange> exchangeCtor =
+					ClassUtils.getConstructorIfAvailable(exchangeType, exchangeParamTypes);
+			if (exchangeCtor != null) {
+				// Undertow 1.1+
+				exchangeConstructor = exchangeCtor;
+				exchangeConstructorWithPeerConnections = true;
+			}
+			else {
+				// Undertow 1.0
+				exchangeParamTypes = new Class<?>[] {HttpServletRequest.class, HttpServletResponse.class};
+				exchangeConstructor = exchangeType.getConstructor(exchangeParamTypes);
+				exchangeConstructorWithPeerConnections = false;
+			}
 
-		Class<ConfiguredServerEndpoint> endpointType = ConfiguredServerEndpoint.class;
-		Class<?>[] endpointParamTypes = new Class<?>[] {ServerEndpointConfig.class, InstanceFactory.class,
-				PathTemplate.class, EncodingFactory.class, AnnotatedEndpointFactory.class};
-		if (ClassUtils.hasConstructor(endpointType, endpointParamTypes)) {
-			endpointConstructor = ClassUtils.getConstructorIfAvailable(endpointType, endpointParamTypes);
-			undertow11Present = true;
+			Class<ConfiguredServerEndpoint> endpointType = ConfiguredServerEndpoint.class;
+			Class<?>[] endpointParamTypes = new Class<?>[] {ServerEndpointConfig.class, InstanceFactory.class,
+					PathTemplate.class, EncodingFactory.class, AnnotatedEndpointFactory.class};
+			Constructor<ConfiguredServerEndpoint> endpointCtor =
+					ClassUtils.getConstructorIfAvailable(endpointType, endpointParamTypes);
+			if (endpointCtor != null) {
+				// Undertow 1.1+
+				endpointConstructor = endpointCtor;
+				endpointConstructorWithEndpointFactory = true;
+			}
+			else {
+				// Undertow 1.0
+				endpointParamTypes = new Class<?>[] {ServerEndpointConfig.class, InstanceFactory.class,
+						PathTemplate.class, EncodingFactory.class};
+				endpointConstructor = endpointType.getConstructor(endpointParamTypes);
+				endpointConstructorWithEndpointFactory = false;
+			}
+
+			// Adapting between different Pool API types in Undertow 1.0-1.2 vs 1.3
+			getBufferPoolMethod = WebSocketHttpExchange.class.getMethod("getBufferPool");
+			createChannelMethod = Handshake.class.getMethod("createChannel",
+					WebSocketHttpExchange.class, StreamConnection.class, getBufferPoolMethod.getReturnType());
 		}
-		else {
-			endpointParamTypes = new Class<?>[] {ServerEndpointConfig.class, InstanceFactory.class,
-					PathTemplate.class, EncodingFactory.class};
-			endpointConstructor = ClassUtils.getConstructorIfAvailable(endpointType, endpointParamTypes);
-			undertow11Present = false;
+		catch (Throwable ex) {
+			throw new IllegalStateException("Incompatible Undertow API version", ex);
 		}
 	}
 
@@ -113,11 +141,11 @@ public class UndertowRequestUpgradeStrategy extends AbstractStandardUpgradeStrat
 
 
 	public UndertowRequestUpgradeStrategy() {
-		if (undertow10Present) {
-			this.peerConnections = null;
+		if (exchangeConstructorWithPeerConnections) {
+			this.peerConnections = Collections.newSetFromMap(new ConcurrentHashMap<WebSocketChannel, Boolean>());
 		}
 		else {
-			this.peerConnections = Collections.newSetFromMap(new ConcurrentHashMap<WebSocketChannel, Boolean>());
+			this.peerConnections = null;
 		}
 	}
 
@@ -149,7 +177,9 @@ protected void upgradeInternal(ServerHttpRequest request, ServerHttpResponse res
 		exchange.upgradeChannel(new HttpUpgradeListener() {
 			@Override
 			public void handleUpgrade(StreamConnection connection, HttpServerExchange serverExchange) {
-				WebSocketChannel channel = handshake.createChannel(exchange, connection, exchange.getBufferPool());
+				Object bufferPool = ReflectionUtils.invokeMethod(getBufferPoolMethod, exchange);
+				WebSocketChannel channel = (WebSocketChannel) ReflectionUtils.invokeMethod(
+						createChannelMethod, handshake, exchange, connection, bufferPool);
 				if (peerConnections != null) {
 					peerConnections.add(channel);
 				}
@@ -202,7 +232,7 @@ private ConfiguredServerEndpoint createConfiguredServerEndpoint(String selectedP
 				Collections.<Class<?>, List<InstanceFactory<? extends Encoder>>>emptyMap(),
 				Collections.<Class<?>, List<InstanceFactory<? extends Decoder>>>emptyMap());
 		try {
-			return (undertow11Present ?
+			return (endpointConstructorWithEndpointFactory ?
 					endpointConstructor.newInstance(endpointRegistration,
 							new EndpointInstanceFactory(endpoint), null, encodingFactory, null) :
 					endpointConstructor.newInstance(endpointRegistration,