Make use of Tomcat's new WsServerContainer.doUpgrade

Tomcat now provides a method for initiating a WebSocket upgrade at
runtime vs relying on JSR-356 deployment at startup. This change
switches to use that latest feature. For more information on the
Tomcat change see:

https://issues.apache.org/bugzilla/show_bug.cgi?id=55314#c7

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

@@ -16,24 +16,21 @@
 
 package org.springframework.web.socket.server.support;
 
-import java.io.IOException;
-import java.lang.reflect.Method;
+import java.util.Arrays;
 import java.util.Collections;
+import java.util.Map;
 
 import javax.servlet.ServletContext;
-import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import javax.websocket.Endpoint;
-import javax.websocket.server.ServerEndpointConfig;
 
-import org.apache.tomcat.websocket.server.WsHandshakeRequest;
-import org.apache.tomcat.websocket.server.WsHttpUpgradeHandler;
 import org.apache.tomcat.websocket.server.WsServerContainer;
 import org.springframework.http.server.ServerHttpRequest;
 import org.springframework.http.server.ServerHttpResponse;
 import org.springframework.http.server.ServletServerHttpRequest;
+import org.springframework.http.server.ServletServerHttpResponse;
 import org.springframework.util.Assert;
-import org.springframework.util.ReflectionUtils;
 import org.springframework.web.socket.server.HandshakeFailureException;
 import org.springframework.web.socket.server.endpoint.ServerEndpointRegistration;
 
@@ -45,6 +42,7 @@ import org.springframework.web.socket.server.endpoint.ServerEndpointRegistration
  */
 public class TomcatRequestUpgradeStrategy extends AbstractStandardUpgradeStrategy {
 
+
 	@Override
 	public String[] getSupportedVersions() {
 		return new String[] { "13" };
@@ -52,37 +50,32 @@ public class TomcatRequestUpgradeStrategy extends AbstractStandardUpgradeStrateg
 
 	@Override
 	public void upgradeInternal(ServerHttpRequest request, ServerHttpResponse response,
-			String acceptedProtocol, Endpoint endpoint) throws IOException {
+			String acceptedProtocol, Endpoint endpoint) throws HandshakeFailureException {
 
 		Assert.isTrue(request instanceof ServletServerHttpRequest);
 		HttpServletRequest servletRequest = ((ServletServerHttpRequest) request).getServletRequest();
 
-		WsHttpUpgradeHandler upgradeHandler;
-		try {
-			upgradeHandler = servletRequest.upgrade(WsHttpUpgradeHandler.class);
-		}
-		catch (ServletException e) {
-			throw new HandshakeFailureException("Unable to create UpgardeHandler", e);
-		}
+		Assert.isTrue(response instanceof ServletServerHttpResponse);
+		HttpServletResponse servletResponse = ((ServletServerHttpResponse) response).getServletResponse();
+
+		String path = servletRequest.getRequestURI(); // shouldn't matter
+		Map<String, String> pathParams = Collections.<String, String> emptyMap();
+
+		ServerEndpointRegistration endpointConfig = new ServerEndpointRegistration(path, endpoint);
+		endpointConfig.setSubprotocols(Arrays.asList(acceptedProtocol));
 
-		WsHandshakeRequest webSocketRequest = new WsHandshakeRequest(servletRequest);
 		try {
-			Method method = ReflectionUtils.findMethod(WsHandshakeRequest.class, "finished");
-			ReflectionUtils.makeAccessible(method);
-			method.invoke(webSocketRequest);
+			getContainer(servletRequest).doUpgrade(servletRequest, servletResponse, endpointConfig, pathParams);
 		}
 		catch (Exception ex) {
 			throw new HandshakeFailureException("Failed to upgrade HttpServletRequest", ex);
 		}
+	}
 
+	private WsServerContainer getContainer(HttpServletRequest servletRequest) {
 		String attribute = "javax.websocket.server.ServerContainer";
 		ServletContext servletContext = servletRequest.getServletContext();
-		WsServerContainer serverContainer = (WsServerContainer) servletContext.getAttribute(attribute);
-
-		ServerEndpointConfig endpointConfig = new ServerEndpointRegistration("/shouldntmatter", endpoint);
-
-		upgradeHandler.preInit(endpoint, endpointConfig, serverContainer, webSocketRequest,
-				acceptedProtocol, Collections.<String, String> emptyMap(), servletRequest.isSecure());
+		return (WsServerContainer) servletContext.getAttribute(attribute);
 	}
 
 }