cn.taketoday.aop.interceptor.ExposeBeanNameAdvisors Maven / Gradle / Ivy
/*
* Original Author -> Harry Yang ([email protected]) https://taketoday.cn
* Copyright © TODAY & 2017 - 2022 All Rights Reserved.
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see [http://www.gnu.org/licenses/]
*/
package cn.taketoday.aop.interceptor;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import cn.taketoday.aop.Advisor;
import cn.taketoday.aop.ProxyMethodInvocation;
import cn.taketoday.aop.support.DefaultIntroductionAdvisor;
import cn.taketoday.aop.support.DefaultPointcutAdvisor;
import cn.taketoday.aop.support.DelegatingIntroductionInterceptor;
import cn.taketoday.beans.factory.NamedBean;
import cn.taketoday.lang.Nullable;
/**
* Convenient methods for creating advisors that may be used when autoproxying beans
* created with the IoC container, binding the bean name to the current
* invocation. May support a {@code bean()} pointcut designator with AspectJ.
*
* Typically used in auto-proxying, where the bean name is known
* at proxy creation time.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @author Harry Yang
* @see NamedBean
* @since 4.0 2022/3/9 22:22
*/
public abstract class ExposeBeanNameAdvisors {
/**
* 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.
*
* @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.
*
* @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 pmi)) {
throw new IllegalArgumentException("MethodInvocation is not a ProxyMethodInvocation: " + mi);
}
String beanName = (String) pmi.getAttribute(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.
*
* @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 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.
*/
private record ExposeBeanNameInterceptor(String beanName) implements MethodInterceptor {
@Override
@Nullable
public Object invoke(MethodInvocation mi) throws Throwable {
if (!(mi instanceof ProxyMethodInvocation pmi)) {
throw new IllegalStateException("MethodInvocation is not a ProxyMethodInvocation: " + mi);
}
pmi.setAttribute(BEAN_NAME_ATTRIBUTE, this.beanName);
return mi.proceed();
}
}
/**
* Introduction that exposes the specified bean name as invocation attribute.
*/
private static class ExposeBeanNameIntroduction extends DelegatingIntroductionInterceptor implements NamedBean {
private final String beanName;
public ExposeBeanNameIntroduction(String beanName) {
this.beanName = beanName;
}
@Override
@Nullable
public Object invoke(MethodInvocation mi) throws Throwable {
if (!(mi instanceof ProxyMethodInvocation pmi)) {
throw new IllegalStateException("MethodInvocation is not a ProxyMethodInvocation: " + mi);
}
pmi.setAttribute(BEAN_NAME_ATTRIBUTE, this.beanName);
return super.invoke(mi);
}
@Override
public String getBeanName() {
return this.beanName;
}
}
}