| /* |
| * 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.cloudstack.framework.async; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import net.sf.cglib.proxy.Enhancer; |
| import net.sf.cglib.proxy.Factory; |
| import net.sf.cglib.proxy.MethodInterceptor; |
| import net.sf.cglib.proxy.MethodProxy; |
| |
| import org.apache.log4j.Logger; |
| |
| @SuppressWarnings("rawtypes") |
| public class AsyncCallbackDispatcher<T, R> implements AsyncCompletionCallback { |
| private static final Logger s_logger = Logger.getLogger(AsyncCallbackDispatcher.class); |
| |
| private Method _callbackMethod; |
| private final T _targetObject; |
| private Object _contextObject; |
| private Object _resultObject; |
| private AsyncCallbackDriver _driver = new InplaceAsyncCallbackDriver(); |
| private static Map<Class, Enhancer> enMap = new HashMap<Class, Enhancer>(); |
| |
| private AsyncCallbackDispatcher(T target) { |
| assert (target != null); |
| _targetObject = target; |
| } |
| |
| public AsyncCallbackDispatcher<T, R> attachDriver(AsyncCallbackDriver driver) { |
| assert (driver != null); |
| _driver = driver; |
| |
| return this; |
| } |
| |
| public Method getCallbackMethod() { |
| return _callbackMethod; |
| } |
| |
| @SuppressWarnings("unchecked") |
| public T getTarget() { |
| Class<?> clz = _targetObject.getClass(); |
| String clzName = clz.getName(); |
| if (clzName.contains("EnhancerByCloudStack")) |
| clz = clz.getSuperclass(); |
| |
| |
| Enhancer en = null; |
| synchronized (enMap) { |
| en = enMap.get(clz); |
| if (en == null) { |
| en = new Enhancer(); |
| |
| en.setSuperclass(clz); |
| en.setCallback(new MethodInterceptor() { |
| @Override |
| public Object intercept(Object arg0, Method arg1, Object[] arg2, MethodProxy arg3) throws Throwable { |
| return null; |
| } |
| }); |
| enMap.put(clz, en); |
| } |
| } |
| |
| try { |
| T t = (T)en.create(); |
| Factory factory = (Factory)t; |
| factory.setCallback(0, new MethodInterceptor() { |
| @Override |
| public Object intercept(Object arg0, Method arg1, Object[] arg2, MethodProxy arg3) throws Throwable { |
| if (arg1.getParameterTypes().length == 0 && arg1.getName().equals("finalize")) { |
| return null; |
| } else { |
| _callbackMethod = arg1; |
| _callbackMethod.setAccessible(true); |
| return null; |
| } |
| } |
| }); |
| return t; |
| } catch (Throwable e) { |
| s_logger.error("Unexpected exception", e); |
| } |
| |
| return null; |
| } |
| |
| public AsyncCallbackDispatcher<T, R> setCallback(Object useless) { |
| return this; |
| } |
| |
| public AsyncCallbackDispatcher<T, R> setContext(Object context) { |
| _contextObject = context; |
| return this; |
| } |
| |
| @SuppressWarnings("unchecked") |
| public <P> P getContext() { |
| return (P)_contextObject; |
| } |
| |
| @Override |
| public void complete(Object resultObject) { |
| _resultObject = resultObject; |
| _driver.performCompletionCallback(this); |
| } |
| |
| @SuppressWarnings("unchecked") |
| public R getResult() { |
| return (R)_resultObject; |
| } |
| |
| // for internal use |
| Object getTargetObject() { |
| return _targetObject; |
| } |
| |
| public static <P, R> AsyncCallbackDispatcher<P, R> create(P target) { |
| return new AsyncCallbackDispatcher<P, R>(target); |
| } |
| |
| public static boolean dispatch(Object target, AsyncCallbackDispatcher callback) { |
| assert (callback != null); |
| assert (target != null); |
| |
| try { |
| callback.getCallbackMethod().invoke(target, callback, callback.getContext()); |
| } catch (IllegalArgumentException e) { |
| throw new RuntimeException("IllegalArgumentException when invoking RPC callback for command: " + callback.getCallbackMethod().getName()); |
| } catch (IllegalAccessException e) { |
| throw new RuntimeException("IllegalAccessException when invoking RPC callback for command: " + callback.getCallbackMethod().getName()); |
| } catch (InvocationTargetException e) { |
| throw new RuntimeException("InvocationTargetException when invoking RPC callback for command: " + callback.getCallbackMethod().getName(), e); |
| } |
| |
| return true; |
| } |
| } |