| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.camel.processor; |
| |
| import org.apache.camel.AsyncCallback; |
| import org.apache.camel.AsyncProcessor; |
| import org.apache.camel.Exchange; |
| import org.apache.camel.Processor; |
| import org.apache.camel.impl.ServiceSupport; |
| import org.apache.camel.impl.converter.AsyncProcessorTypeConverter; |
| import org.apache.camel.util.AsyncProcessorHelper; |
| import org.apache.camel.util.ServiceHelper; |
| |
| /** |
| * A bridge to have regular interceptors implemented as {@link org.apache.camel.Processor} |
| * work with the asynchronous routing engine without causing side effects. |
| * |
| * @version |
| */ |
| public class InterceptorToAsyncProcessorBridge extends ServiceSupport implements AsyncProcessor { |
| |
| private final AsyncProcessor interceptor; |
| private volatile AsyncProcessor target; |
| private volatile ThreadLocal<AsyncCallback> callback = new ThreadLocal<AsyncCallback>(); |
| private volatile ThreadLocal<Boolean> interceptorDone = new ThreadLocal<Boolean>(); |
| |
| /** |
| * Constructs the bridge |
| * |
| * @param interceptor the interceptor to bridge |
| */ |
| public InterceptorToAsyncProcessorBridge(Processor interceptor) { |
| this(interceptor, null); |
| } |
| |
| /** |
| * Constructs the bridge |
| * |
| * @param interceptor the interceptor to bridge |
| * @param target the target |
| */ |
| public InterceptorToAsyncProcessorBridge(Processor interceptor, AsyncProcessor target) { |
| this.interceptor = AsyncProcessorTypeConverter.convert(interceptor); |
| this.target = target; |
| } |
| |
| /** |
| * Process invoked by the interceptor |
| * @param exchange the message exchange |
| * @throws Exception |
| */ |
| public void process(Exchange exchange) throws Exception { |
| // invoke when interceptor wants to invoke |
| boolean done = interceptor.process(exchange, callback.get()); |
| interceptorDone.set(done); |
| } |
| |
| public boolean process(Exchange exchange, AsyncCallback callback) { |
| // remember the callback to be used by the interceptor |
| this.callback.set(callback); |
| try { |
| // invoke the target |
| boolean done = target.process(exchange, callback); |
| if (interceptorDone.get() != null) { |
| // return the result from the interceptor if it was invoked |
| return interceptorDone.get(); |
| } else { |
| // otherwise from the target |
| return done; |
| } |
| } finally { |
| // cleanup |
| this.callback.remove(); |
| this.interceptorDone.remove(); |
| } |
| } |
| |
| public void setTarget(Processor target) { |
| this.target = AsyncProcessorTypeConverter.convert(target); |
| } |
| |
| @Override |
| public String toString() { |
| return "AsyncBridge[" + interceptor.toString() + "]"; |
| } |
| |
| @Override |
| protected void doStart() throws Exception { |
| ServiceHelper.startServices(target, interceptor); |
| } |
| |
| @Override |
| protected void doStop() throws Exception { |
| callback.remove(); |
| interceptorDone.remove(); |
| ServiceHelper.stopServices(interceptor, target); |
| } |
| } |