/*
* Copyright 2002-2008 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.aop.aspectj;
import java.util.List;
import org.springframework.aop.Advisor;
import org.springframework.aop.PointcutAdvisor;
import org.springframework.aop.interceptor.ExposeInvocationInterceptor;
/**
* Utility methods for working with AspectJ proxies.
*
* @author Rod Johnson
* @author Ramnivas Laddad
* @since 2.0
*/
public abstract class AspectJProxyUtils {
/**
* Add special advisors if necessary to work with a proxy chain that contains AspectJ advisors.
* This will expose the current Spring AOP invocation (necessary for some AspectJ pointcut matching)
* and make available the current AspectJ JoinPoint. The call will have no effect if there are no
* AspectJ advisors in the advisor chain.
* @param advisors Advisors available
* @return <code>true</code> if any special {@link Advisor Advisors} were added, otherwise <code>false</code>.
*/
public static boolean makeAdvisorChainAspectJCapableIfNecessary(List<Advisor> advisors) {
// Don't add advisors to an empty list; may indicate that proxying is just not required
if (!advisors.isEmpty()) {
boolean foundAspectJAdvice = false;
for (Advisor advisor : advisors) {
// Be careful not to get the Advice without a guard, as
// this might eagerly instantiate a non-singleton AspectJ aspect
if (isAspectJAdvice(advisor)) {
foundAspectJAdvice = true;
}
}
if (foundAspectJAdvice && !advisors.contains(ExposeInvocationInterceptor.ADVISOR)) {
advisors.add(0, ExposeInvocationInterceptor.ADVISOR);
return true;
}
}
return false;
}
/**
* Determine whether the given Advisor contains an AspectJ advice.
* @param advisor the Advisor to check
*/
private static boolean isAspectJAdvice(Advisor advisor) {
return (advisor instanceof InstantiationModelAwarePointcutAdvisor ||
advisor.getAdvice() instanceof AbstractAspectJAdvice ||
(advisor instanceof PointcutAdvisor &&
((PointcutAdvisor) advisor).getPointcut() instanceof AspectJExpressionPointcut));
}
}
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