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/* * Copyright 2002-2017 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 * * https://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; import org.aopalliance.aop.Advice; /** * Base interface holding AOP <b>advice</b> (action to take at a joinpoint) * and a filter determining the applicability of the advice (such as * a pointcut). <i>This interface is not for use by Spring users, but to * allow for commonality in support for different types of advice.</i> * * <p>Spring AOP is based around <b>around advice</b> delivered via method * <b>interception</b>, compliant with the AOP Alliance interception API. * The Advisor interface allows support for different types of advice, * such as <b>before</b> and <b>after</b> advice, which need not be * implemented using interception. * * @author Rod Johnson * @author Juergen Hoeller */ public interface Advisor { /** * Common placeholder for an empty {@code Advice} to be returned from * {@link #getAdvice()} if no proper advice has been configured (yet). * @since 5.0 */ Advice EMPTY_ADVICE = new Advice() { }; /** * Return the advice part of this aspect. An advice may be an * interceptor, a before advice, a throws advice, etc. * @return the advice that should apply if the pointcut matches * @see org.aopalliance.intercept.MethodInterceptor * @see BeforeAdvice * @see ThrowsAdvice * @see AfterReturningAdvice */ Advice getAdvice(); /** * Return whether this advice is associated with a particular instance * (for example, creating a mixin) or shared with all instances of * the advised class obtained from the same Spring bean factory. * <p><b>Note that this method is not currently used by the framework.</b> * Typical Advisor implementations always return {@code true}. * Use singleton/prototype bean definitions or appropriate programmatic * proxy creation to ensure that Advisors have the correct lifecycle model. * @return whether this advice is associated with a particular target instance */ boolean isPerInstance(); }