org.springframework.context.annotation.EnableAspectJAutoProxy Maven / Gradle / Ivy
/*
* Copyright 2002-2021 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.context.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Enables support for handling components marked with AspectJ's {@code @Aspect} annotation,
* similar to functionality found in Spring's {@code } XML element.
* To be used on @{@link Configuration} classes as follows:
*
*
* @Configuration
* @EnableAspectJAutoProxy
* public class AppConfig {
*
* @Bean
* public FooService fooService() {
* return new FooService();
* }
*
* @Bean
* public MyAspect myAspect() {
* return new MyAspect();
* }
* }
*
* Where {@code FooService} is a typical POJO component and {@code MyAspect} is an
* {@code @Aspect}-style aspect:
*
*
* public class FooService {
*
* // various methods
* }
*
*
* @Aspect
* public class MyAspect {
*
* @Before("execution(* FooService+.*(..))")
* public void advice() {
* // advise FooService methods as appropriate
* }
* }
*
* In the scenario above, {@code @EnableAspectJAutoProxy} ensures that {@code MyAspect}
* will be properly processed and that {@code FooService} will be proxied mixing in the
* advice that it contributes.
*
* Users can control the type of proxy that gets created for {@code FooService} using
* the {@link #proxyTargetClass()} attribute. The following enables CGLIB-style 'subclass'
* proxies as opposed to the default interface-based JDK proxy approach.
*
*
* @Configuration
* @EnableAspectJAutoProxy(proxyTargetClass=true)
* public class AppConfig {
* // ...
* }
*
* Note that {@code @Aspect} beans may be component-scanned like any other.
* Simply mark the aspect with both {@code @Aspect} and {@code @Component}:
*
*
* package com.foo;
*
* @Component
* public class FooService { ... }
*
* @Aspect
* @Component
* public class MyAspect { ... }
*
* Then use the @{@link ComponentScan} annotation to pick both up:
*
*
* @Configuration
* @ComponentScan("com.foo")
* @EnableAspectJAutoProxy
* public class AppConfig {
*
* // no explicit @Bean definitions required
* }
*
* Note: {@code @EnableAspectJAutoProxy} applies to its local application context only,
* allowing for selective proxying of beans at different levels. Please redeclare
* {@code @EnableAspectJAutoProxy} in each individual context, for example, the common root web
* application context and any separate {@code DispatcherServlet} application contexts,
* if you need to apply its behavior at multiple levels.
*
* This feature requires the presence of {@code aspectjweaver} on the classpath.
* While that dependency is optional for {@code spring-aop} in general, it is required
* for {@code @EnableAspectJAutoProxy} and its underlying facilities.
*
* @author Chris Beams
* @author Juergen Hoeller
* @since 3.1
* @see org.aspectj.lang.annotation.Aspect
*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Import(AspectJAutoProxyRegistrar.class)
public @interface EnableAspectJAutoProxy {
/**
* Indicate whether subclass-based (CGLIB) proxies are to be created as opposed
* to standard Java interface-based proxies. The default is {@code false}.
*/
boolean proxyTargetClass() default false;
/**
* Indicate that the proxy should be exposed by the AOP framework as a {@code ThreadLocal}
* for retrieval via the {@link org.springframework.aop.framework.AopContext} class.
* Off by default, i.e. no guarantees that {@code AopContext} access will work.
* @since 4.3.1
*/
boolean exposeProxy() default false;
}