001/* 002 * Copyright 2002-2019 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.aop.aspectj; 018 019import java.util.List; 020 021import org.springframework.aop.Advisor; 022import org.springframework.aop.PointcutAdvisor; 023import org.springframework.aop.interceptor.ExposeInvocationInterceptor; 024 025/** 026 * Utility methods for working with AspectJ proxies. 027 * 028 * @author Rod Johnson 029 * @author Ramnivas Laddad 030 * @author Juergen Hoeller 031 * @since 2.0 032 */ 033public abstract class AspectJProxyUtils { 034 035 /** 036 * Add special advisors if necessary to work with a proxy chain that contains AspectJ advisors: 037 * concretely, {@link ExposeInvocationInterceptor} at the beginning of the list. 038 * <p>This will expose the current Spring AOP invocation (necessary for some AspectJ pointcut 039 * matching) and make available the current AspectJ JoinPoint. The call will have no effect 040 * if there are no AspectJ advisors in the advisor chain. 041 * @param advisors the advisors available 042 * @return {@code true} if an {@link ExposeInvocationInterceptor} was added to the list, 043 * otherwise {@code false} 044 */ 045 public static boolean makeAdvisorChainAspectJCapableIfNecessary(List<Advisor> advisors) { 046 // Don't add advisors to an empty list; may indicate that proxying is just not required 047 if (!advisors.isEmpty()) { 048 boolean foundAspectJAdvice = false; 049 for (Advisor advisor : advisors) { 050 // Be careful not to get the Advice without a guard, as this might eagerly 051 // instantiate a non-singleton AspectJ aspect... 052 if (isAspectJAdvice(advisor)) { 053 foundAspectJAdvice = true; 054 break; 055 } 056 } 057 if (foundAspectJAdvice && !advisors.contains(ExposeInvocationInterceptor.ADVISOR)) { 058 advisors.add(0, ExposeInvocationInterceptor.ADVISOR); 059 return true; 060 } 061 } 062 return false; 063 } 064 065 /** 066 * Determine whether the given Advisor contains an AspectJ advice. 067 * @param advisor the Advisor to check 068 */ 069 private static boolean isAspectJAdvice(Advisor advisor) { 070 return (advisor instanceof InstantiationModelAwarePointcutAdvisor || 071 advisor.getAdvice() instanceof AbstractAspectJAdvice || 072 (advisor instanceof PointcutAdvisor && 073 ((PointcutAdvisor) advisor).getPointcut() instanceof AspectJExpressionPointcut)); 074 } 075 076}