001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.camel.util.concurrent; 018 019 import java.util.List; 020 import java.util.concurrent.AbstractExecutorService; 021 import java.util.concurrent.TimeUnit; 022 023 /** 024 * A synchronous {@link java.util.concurrent.ExecutorService} which always invokes 025 * the task in the caller thread (just a thread pool facade). 026 * <p/> 027 * There is no task queue, and no thread pool. The task will thus always be executed 028 * by the caller thread in a fully synchronous method invocation. 029 * <p/> 030 * This implementation is very simple and does not support waiting for tasks to complete during shutdown. 031 * 032 * @version 033 */ 034 public class SynchronousExecutorService extends AbstractExecutorService { 035 036 private volatile boolean shutdown; 037 038 public void shutdown() { 039 shutdown = true; 040 } 041 042 public List<Runnable> shutdownNow() { 043 // not implemented 044 return null; 045 } 046 047 public boolean isShutdown() { 048 return shutdown; 049 } 050 051 public boolean isTerminated() { 052 return shutdown; 053 } 054 055 public boolean awaitTermination(long time, TimeUnit unit) throws InterruptedException { 056 // not implemented 057 return true; 058 } 059 060 public void execute(Runnable runnable) { 061 // run the task synchronously 062 runnable.run(); 063 } 064 065 }