/*
* Copyright 2002-2011 the original author or authors.
*
* 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 org.springframework.flex.core;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.Stack;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import flex.messaging.messages.Message;
/**
* AOP interceptor that applies any provided {@link MessageInterceptor}s to the AMF {@link Message} being processed.
*
* @author Jeremy Grelle
*/
public class MessageInterceptionAdvice implements MethodInterceptor {
private Set<MessageInterceptor> messageInterceptors = new LinkedHashSet<MessageInterceptor>();
/**
* Returns the chain of provided {@link MessageInterceptor}s
*
* @return the message interceptors
*/
public Set<MessageInterceptor> getMessageInterceptors() {
return this.messageInterceptors;
}
/**
*
* {@inheritDoc}
*/
public Object invoke(MethodInvocation mi) throws Throwable {
MessageProcessingContext context = new MessageProcessingContext(mi.getThis());
Message inputMessage = (Message) mi.getArguments()[0];
Message outputMessage = null;
Stack<ResourceHandlingMessageInterceptor> resourceHandlerStack = new Stack<ResourceHandlingMessageInterceptor>();
try {
for (MessageInterceptor interceptor : this.messageInterceptors) {
if (interceptor instanceof ResourceHandlingMessageInterceptor) {
resourceHandlerStack.add((ResourceHandlingMessageInterceptor) interceptor);
}
inputMessage = interceptor.preProcess(context, inputMessage);
}
mi.getArguments()[0] = inputMessage;
outputMessage = (Message) mi.proceed();
if (outputMessage != null) {
Stack<MessageInterceptor> postProcessStack = new Stack<MessageInterceptor>();
postProcessStack.addAll(this.messageInterceptors);
while (!postProcessStack.empty()) {
MessageInterceptor interceptor = postProcessStack.pop();
outputMessage = interceptor.postProcess(context, inputMessage, outputMessage);
}
}
} catch (Exception ex) {
doAfterComplete(resourceHandlerStack, context, inputMessage, outputMessage, ex);
throw ex;
}
doAfterComplete(resourceHandlerStack, context, inputMessage, outputMessage, null);
return outputMessage;
}
/**
* Sets the chain of provided {@link MessageInterceptor}s
*
* @param messageInterceptors the message interceptors
*/
public void setMessageInterceptors(Set<MessageInterceptor> messageInterceptors) {
this.messageInterceptors = messageInterceptors;
}
private void doAfterComplete(Stack<ResourceHandlingMessageInterceptor> resourceHandlerStack, MessageProcessingContext context,
Message inputMessage, Message outputMessage, Exception ex) {
while (!resourceHandlerStack.empty()) {
resourceHandlerStack.pop().afterCompletion(context, inputMessage, outputMessage, ex);
}
}
}