https://github.com/spring-projects/spring-framework: Spring AOP (Spring IO)
  • Juergen Hoeller 
/*
 * Copyright 2002-2018 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.interceptor;

import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;

import org.springframework.aop.Advisor;
import org.springframework.aop.ProxyMethodInvocation;
import org.springframework.aop.support.DefaultIntroductionAdvisor;
import org.springframework.aop.support.DefaultPointcutAdvisor;
import org.springframework.aop.support.DelegatingIntroductionInterceptor;
import org.springframework.beans.factory.NamedBean;


Convenient methods for creating advisors that may be used when autoproxying beans created with the Spring IoC container, binding the bean name to the current invocation. May support a bean() pointcut designator with AspectJ. 
Typically used in Spring auto-proxying, where the bean name is known
at proxy creation time.

Author:Rod Johnson, Juergen Hoeller
See Also:
Since:2.0
/**
 * Convenient methods for creating advisors that may be used when autoproxying beans
 * created with the Spring IoC container, binding the bean name to the current
 * invocation. May support a {@code bean()} pointcut designator with AspectJ.
 *
 * <p>Typically used in Spring auto-proxying, where the bean name is known
 * at proxy creation time.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 2.0
 * @see org.springframework.beans.factory.NamedBean
 */
public abstract class ExposeBeanNameAdvisors {

	
Binding for the bean name of the bean which is currently being invoked
in the ReflectiveMethodInvocation userAttributes Map.

/**
	 * Binding for the bean name of the bean which is currently being invoked
	 * in the ReflectiveMethodInvocation userAttributes Map.
	 */
	private static final String BEAN_NAME_ATTRIBUTE = ExposeBeanNameAdvisors.class.getName() + ".BEAN_NAME";


	
Find the bean name for the current invocation. Assumes that an ExposeBeanNameAdvisor
has been included in the interceptor chain, and that the invocation is exposed
with ExposeInvocationInterceptor.

Throws:
Returns:the bean name (never null)
/**
	 * Find the bean name for the current invocation. Assumes that an ExposeBeanNameAdvisor
	 * has been included in the interceptor chain, and that the invocation is exposed
	 * with ExposeInvocationInterceptor.
	 * @return the bean name (never {@code null})
	 * @throws IllegalStateException if the bean name has not been exposed
	 */
	public static String getBeanName() throws IllegalStateException {
		return getBeanName(ExposeInvocationInterceptor.currentInvocation());
	}

	
Find the bean name for the given invocation. Assumes that an ExposeBeanNameAdvisor
has been included in the interceptor chain.

Params:
  • mi – the MethodInvocation that should contain the bean name as an attribute
Throws:
Returns:the bean name (never null)
/**
	 * Find the bean name for the given invocation. Assumes that an ExposeBeanNameAdvisor
	 * has been included in the interceptor chain.
	 * @param mi the MethodInvocation that should contain the bean name as an attribute
	 * @return the bean name (never {@code null})
	 * @throws IllegalStateException if the bean name has not been exposed
	 */
	public static String getBeanName(MethodInvocation mi) throws IllegalStateException {
		if (!(mi instanceof ProxyMethodInvocation)) {
			throw new IllegalArgumentException("MethodInvocation is not a Spring ProxyMethodInvocation: " + mi);
		}
		ProxyMethodInvocation pmi = (ProxyMethodInvocation) mi;
		String beanName = (String) pmi.getUserAttribute(BEAN_NAME_ATTRIBUTE);
		if (beanName == null) {
			throw new IllegalStateException("Cannot get bean name; not set on MethodInvocation: " + mi);
		}
		return beanName;
	}

	
Create a new advisor that will expose the given bean name,
with no introduction.

Params:
  • beanName – bean name to expose
/**
	 * Create a new advisor that will expose the given bean name,
	 * with no introduction.
	 * @param beanName bean name to expose
	 */
	public static Advisor createAdvisorWithoutIntroduction(String beanName) {
		return new DefaultPointcutAdvisor(new ExposeBeanNameInterceptor(beanName));
	}

	
Create a new advisor that will expose the given bean name, introducing
the NamedBean interface to make the bean name accessible without forcing
the target object to be aware of this Spring IoC concept.

Params:
  • beanName – the bean name to expose
/**
	 * Create a new advisor that will expose the given bean name, introducing
	 * the NamedBean interface to make the bean name accessible without forcing
	 * the target object to be aware of this Spring IoC concept.
	 * @param beanName the bean name to expose
	 */
	public static Advisor createAdvisorIntroducingNamedBean(String beanName) {
		return new DefaultIntroductionAdvisor(new ExposeBeanNameIntroduction(beanName));
	}


	
Interceptor that exposes the specified bean name as invocation attribute.

/**
	 * Interceptor that exposes the specified bean name as invocation attribute.
	 */
	private static class ExposeBeanNameInterceptor implements MethodInterceptor {

		private final String beanName;

		public ExposeBeanNameInterceptor(String beanName) {
			this.beanName = beanName;
		}

		@Override
		public Object invoke(MethodInvocation mi) throws Throwable {
			if (!(mi instanceof ProxyMethodInvocation)) {
				throw new IllegalStateException("MethodInvocation is not a Spring ProxyMethodInvocation: " + mi);
			}
			ProxyMethodInvocation pmi = (ProxyMethodInvocation) mi;
			pmi.setUserAttribute(BEAN_NAME_ATTRIBUTE, this.beanName);
			return mi.proceed();
		}
	}


	
Introduction that exposes the specified bean name as invocation attribute.

/**
	 * Introduction that exposes the specified bean name as invocation attribute.
	 */
	@SuppressWarnings("serial")
	private static class ExposeBeanNameIntroduction extends DelegatingIntroductionInterceptor implements NamedBean {

		private final String beanName;

		public ExposeBeanNameIntroduction(String beanName) {
			this.beanName = beanName;
		}

		@Override
		public Object invoke(MethodInvocation mi) throws Throwable {
			if (!(mi instanceof ProxyMethodInvocation)) {
				throw new IllegalStateException("MethodInvocation is not a Spring ProxyMethodInvocation: " + mi);
			}
			ProxyMethodInvocation pmi = (ProxyMethodInvocation) mi;
			pmi.setUserAttribute(BEAN_NAME_ATTRIBUTE, this.beanName);
			return super.invoke(mi);
		}

		@Override
		public String getBeanName() {
			return this.beanName;
		}
	}

}