001 /** 002 * 003 * Copyright 2004 Protique Ltd 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * 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 **/ 018 019 package org.activemq.util; 020 021 import EDU.oswego.cs.dl.util.concurrent.Executor; 022 import org.apache.commons.logging.Log; 023 import org.apache.commons.logging.LogFactory; 024 025 import java.lang.reflect.InvocationHandler; 026 import java.lang.reflect.Method; 027 import java.lang.reflect.Proxy; 028 029 /** 030 * A proxy to some service which offers an asynchronous way to invoke methods which 031 * are void and don't throw exceptions. Calling the method results in a command object 032 * being added to a queue for later execution. 033 * 034 * @version $Revision: 1.1.1.1 $ 035 */ 036 public class AsyncProxy implements InvocationHandler { 037 038 private Object realObject; 039 private Executor executor; 040 private Log log; 041 042 public static Object createProxy(Class interfaceType, Object realObject, Executor executor) { 043 return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(), 044 new Class[]{interfaceType}, 045 new AsyncProxy(realObject, executor)); 046 } 047 048 public AsyncProxy(Object realObject, Executor executor) { 049 this(realObject, executor, LogFactory.getLog(AsyncProxy.class)); 050 } 051 052 public AsyncProxy(Object realObject, Executor executor, Log log) { 053 this.realObject = realObject; 054 this.executor = executor; 055 this.log = log; 056 } 057 058 public AsyncProxy(Executor executor, Log log) { 059 this.executor = executor; 060 this.log = log; 061 } 062 063 public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable { 064 if (method.getReturnType() == void.class) { 065 executor.execute(new Runnable() { 066 public void run() { 067 doAsyncMethodInvoke(method, args); 068 } 069 }); 070 return null; 071 } 072 else { 073 return method.invoke(realObject, args); 074 } 075 } 076 077 protected void doAsyncMethodInvoke(Method method, Object[] args) { 078 try { 079 method.invoke(realObject, args); 080 } 081 catch (Throwable e) { 082 log.warn("Caught exception: " + e, e); 083 } 084 } 085 }