/*
* Copyright 1999-2011 Alibaba Group.
*
* Licensed 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 com.alibaba.dubbo.rpc.protocol.dubbo.filter;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.concurrent.Future;
import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.extension.Activate;
import com.alibaba.dubbo.common.logger.Logger;
import com.alibaba.dubbo.common.logger.LoggerFactory;
import com.alibaba.dubbo.remoting.exchange.ResponseCallback;
import com.alibaba.dubbo.remoting.exchange.ResponseFuture;
import com.alibaba.dubbo.rpc.Filter;
import com.alibaba.dubbo.rpc.Invocation;
import com.alibaba.dubbo.rpc.Invoker;
import com.alibaba.dubbo.rpc.Result;
import com.alibaba.dubbo.rpc.RpcContext;
import com.alibaba.dubbo.rpc.RpcException;
import com.alibaba.dubbo.rpc.StaticContext;
import com.alibaba.dubbo.rpc.protocol.dubbo.FutureAdapter;
import com.alibaba.dubbo.rpc.support.RpcUtils;
/**
* EventFilter
* @author chao.liuc
* @author william.liangf
*/
@Activate(group = Constants.CONSUMER)
public class FutureFilter implements Filter {
protected static final Logger logger = LoggerFactory.getLogger(FutureFilter.class);
public Result invoke(final Invoker<?> invoker, final Invocation invocation) throws RpcException {
final boolean isAsync = RpcUtils.isAsync(invoker.getUrl(), invocation);
fireInvokeCallback(invoker, invocation);
//需要在调用前配置好是否有返回值，已供invoker判断是否需要返回future.
Result result = invoker.invoke(invocation);
if (isAsync) {
asyncCallback(invoker, invocation);
} else {
syncCallback(invoker, invocation, result);
}
return result;
}
private void syncCallback(final Invoker<?> invoker, final Invocation invocation, final Result result) {
if (result.hasException()) {
fireThrowCallback(invoker, invocation, result.getException());
} else {
fireReturnCallback(invoker, invocation, result.getValue());
}
}
private void asyncCallback(final Invoker<?> invoker, final Invocation invocation) {
Future<?> f = RpcContext.getContext().getFuture();
if (f instanceof FutureAdapter) {
ResponseFuture future = ((FutureAdapter<?>)f).getFuture();
future.setCallback(new ResponseCallback() {
public void done(Object rpcResult) {
if (rpcResult == null){
logger.error(new IllegalStateException("invalid result value : null, expected "+Result.class.getName()));
return;
}
///must be rpcResult
if (! (rpcResult instanceof Result)){
logger.error(new IllegalStateException("invalid result type :" + rpcResult.getClass() + ", expected "+Result.class.getName()));
return;
}
Result result = (Result) rpcResult;
if (result.hasException()) {
fireThrowCallback(invoker, invocation, result.getException());
} else {
fireReturnCallback(invoker, invocation, result.getValue());
}
}
public void caught(Throwable exception) {
fireThrowCallback(invoker, invocation, exception);
}
});
}
}
private void fireInvokeCallback(final Invoker<?> invoker, final Invocation invocation) {
final Method onInvokeMethod = (Method)StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_INVOKE_METHOD_KEY));
final Object onInvokeInst = StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_INVOKE_INSTANCE_KEY));
if (onInvokeMethod == null && onInvokeInst == null ){
return ;
}
if (onInvokeMethod == null || onInvokeInst == null ){
throw new IllegalStateException("service:" + invoker.getUrl().getServiceKey() +" has a onreturn callback config , but no such "+(onInvokeMethod == null ? "method" : "instance")+" found. url:"+invoker.getUrl());
}
if (onInvokeMethod != null && ! onInvokeMethod.isAccessible()) {
onInvokeMethod.setAccessible(true);
}
Object[] params = invocation.getArguments();
try {
onInvokeMethod.invoke(onInvokeInst, params);
} catch (InvocationTargetException e) {
fireThrowCallback(invoker, invocation, e.getTargetException());
} catch (Throwable e) {
fireThrowCallback(invoker, invocation, e);
}
}
private void fireReturnCallback(final Invoker<?> invoker, final Invocation invocation, final Object result) {
final Method onReturnMethod = (Method)StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_RETURN_METHOD_KEY));
final Object onReturnInst = StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_RETURN_INSTANCE_KEY));
//not set onreturn callback
if (onReturnMethod == null && onReturnInst == null ){
return ;
}
if (onReturnMethod == null || onReturnInst == null ){
throw new IllegalStateException("service:" + invoker.getUrl().getServiceKey() +" has a onreturn callback config , but no such "+(onReturnMethod == null ? "method" : "instance")+" found. url:"+invoker.getUrl());
}
if (onReturnMethod != null && ! onReturnMethod.isAccessible()) {
onReturnMethod.setAccessible(true);
}
Object[] args = invocation.getArguments();
Object[] params ;
Class<?>[] rParaTypes = onReturnMethod.getParameterTypes() ;
if (rParaTypes.length >1 ) {
if (rParaTypes.length == 2 && rParaTypes[1].isAssignableFrom(Object[].class)){
params = new Object[2];
params[0] = result;
params[1] = args ;
}else {
params = new Object[args.length + 1];
params[0] = result;
System.arraycopy(args, 0, params, 1, args.length);
}
} else {
params = new Object[] { result };
}
try {
onReturnMethod.invoke(onReturnInst, params);
} catch (InvocationTargetException e) {
fireThrowCallback(invoker, invocation, e.getTargetException());
} catch (Throwable e) {
fireThrowCallback(invoker, invocation, e);
}
}
private void fireThrowCallback(final Invoker<?> invoker, final Invocation invocation, final Throwable exception) {
final Method onthrowMethod = (Method)StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_THROW_METHOD_KEY));
final Object onthrowInst = StaticContext.getSystemContext().get(StaticContext.getKey(invoker.getUrl(), invocation.getMethodName(), Constants.ON_THROW_INSTANCE_KEY));
//没有设置onthrow callback.
if (onthrowMethod == null && onthrowInst == null ){
return ;
}
if (onthrowMethod == null || onthrowInst == null ){
throw new IllegalStateException("service:" + invoker.getUrl().getServiceKey() +" has a onthrow callback config , but no such "+(onthrowMethod == null ? "method" : "instance")+" found. url:"+invoker.getUrl());
}
if (onthrowMethod != null && ! onthrowMethod.isAccessible()) {
onthrowMethod.setAccessible(true);
}
Class<?>[] rParaTypes = onthrowMethod.getParameterTypes() ;
if (rParaTypes[0].isAssignableFrom(exception.getClass())){
try {
Object[] args = invocation.getArguments();
Object[] params;
if (rParaTypes.length >1 ) {
if (rParaTypes.length == 2 && rParaTypes[1].isAssignableFrom(Object[].class)){
params = new Object[2];
params[0] = exception;
params[1] = args ;
}else {
params = new Object[args.length + 1];
params[0] = exception;
System.arraycopy(args, 0, params, 1, args.length);
}
} else {
params = new Object[] { exception };
}
onthrowMethod.invoke(onthrowInst,params);
} catch (Throwable e) {
logger.error(invocation.getMethodName() +".call back method invoke error . callback method :" + onthrowMethod + ", url:"+ invoker.getUrl(), e);
}
} else {
logger.error(invocation.getMethodName() +".call back method invoke error . callback method :" + onthrowMethod + ", url:"+ invoker.getUrl(), exception);
}
}
}