cn.taketoday.aop.framework.autoproxy.AbstractAdvisorAutoProxyCreator 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.framework.autoproxy;
import java.util.List;
import cn.taketoday.aop.Advisor;
import cn.taketoday.aop.TargetSource;
import cn.taketoday.aop.support.AopUtils;
import cn.taketoday.beans.factory.BeanFactory;
import cn.taketoday.beans.factory.config.ConfigurableBeanFactory;
import cn.taketoday.core.annotation.AnnotationAwareOrderComparator;
import cn.taketoday.core.annotation.Order;
import cn.taketoday.lang.Assert;
import cn.taketoday.lang.Nullable;
/**
* Generic auto proxy creator that builds AOP proxies for specific beans
* based on detected Advisors for each bean.
*
* Subclasses may override the {@link #findCandidateAdvisors()} method to
* return a custom list of Advisors applying to any object. Subclasses can
* also override the inherited {@link #shouldSkip} method to exclude certain
* objects from auto-proxying.
*
*
Advisors or advices requiring ordering should be annotated with
* {@link Order @Order} or implement the
* {@link cn.taketoday.core.Ordered} interface. This class sorts
* advisors using the {@link cn.taketoday.core.annotation.AnnotationAwareOrderComparator}. Advisors that are
* not annotated with {@code @Order} or don't implement the {@code Ordered}
* interface will be considered as unordered; they will appear at the end of the
* advisor chain in an undefined order.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @author Harry Yang
* @see #findCandidateAdvisors
* @since 4.0
*/
@SuppressWarnings("serial")
public abstract class AbstractAdvisorAutoProxyCreator extends AbstractAutoProxyCreator {
@Nullable
private BeanFactoryAdvisorRetriever advisorRetriever;
@Override
public void setBeanFactory(BeanFactory beanFactory) {
super.setBeanFactory(beanFactory);
if (!(beanFactory instanceof ConfigurableBeanFactory)) {
throw new IllegalArgumentException(
"AdvisorAutoProxyCreator requires a ConfigurableBeanFactory: " + beanFactory);
}
initBeanFactory((ConfigurableBeanFactory) beanFactory);
}
protected void initBeanFactory(ConfigurableBeanFactory beanFactory) {
this.advisorRetriever = new BeanFactoryAdvisorRetrieverAdapter(beanFactory);
}
@Override
@Nullable
protected Object[] getAdvicesAndAdvisorsForBean(
Class beanClass, String beanName, @Nullable TargetSource targetSource) {
List advisors = findEligibleAdvisors(beanClass, beanName);
if (advisors.isEmpty()) {
return DO_NOT_PROXY;
}
return advisors.toArray();
}
/**
* Find all eligible Advisors for auto-proxying this class.
*
* @param beanClass the clazz to find advisors for
* @param beanName the name of the currently proxied bean
* @return the empty List, not {@code null},
* if there are no pointcuts or interceptors
* @see #findCandidateAdvisors
* @see #sortAdvisors(List)
* @see #extendAdvisors(List)
*/
protected List findEligibleAdvisors(Class beanClass, String beanName) {
List candidateAdvisors = findCandidateAdvisors();
List eligibleAdvisors = findAdvisorsThatCanApply(candidateAdvisors, beanClass, beanName);
extendAdvisors(eligibleAdvisors);
if (!eligibleAdvisors.isEmpty()) {
eligibleAdvisors = sortAdvisors(eligibleAdvisors);
}
return eligibleAdvisors;
}
/**
* Find all candidate Advisors to use in auto-proxying.
*
* @return the List of candidate Advisors
*/
protected List findCandidateAdvisors() {
Assert.state(this.advisorRetriever != null, "No BeanFactoryAdvisorRetriever available");
return this.advisorRetriever.retrieveAdvisorBeans();
}
/**
* Search the given candidate Advisors to find all Advisors that
* can apply to the specified bean.
*
* @param candidateAdvisors the candidate Advisors
* @param beanClass the target's bean class
* @param beanName the target's bean name
* @return the List of applicable Advisors
* @see ProxyCreationContext#getCurrentProxiedBeanName()
*/
protected List findAdvisorsThatCanApply(
List candidateAdvisors, Class beanClass, String beanName) {
ProxyCreationContext.setCurrentProxiedBeanName(beanName);
try {
return AopUtils.filterAdvisors(candidateAdvisors, beanClass);
}
finally {
ProxyCreationContext.setCurrentProxiedBeanName(null);
}
}
/**
* Return whether the Advisor bean with the given name is eligible
* for proxying in the first place.
*
* @param beanName the name of the Advisor bean
* @return whether the bean is eligible
*/
protected boolean isEligibleAdvisorBean(String beanName) {
return true;
}
/**
* Sort advisors based on ordering. Subclasses may choose to override this
* method to customize the sorting strategy.
*
* @param advisors the source List of Advisors
* @return the sorted List of Advisors
* @see cn.taketoday.core.Ordered
* @see Order
* @see cn.taketoday.core.annotation.AnnotationAwareOrderComparator
*/
protected List sortAdvisors(List advisors) {
AnnotationAwareOrderComparator.sort(advisors);
return advisors;
}
/**
* Extension hook that subclasses can override to register additional Advisors,
* given the sorted Advisors obtained to date.
* The default implementation is empty.
*
Typically used to add Advisors that expose contextual information
* required by some of the later advisors.
*
* @param candidateAdvisors the Advisors that have already been identified as
* applying to a given bean
*/
protected void extendAdvisors(List candidateAdvisors) { }
/**
* This auto-proxy creator always returns pre-filtered Advisors.
*/
@Override
protected boolean advisorsPreFiltered() {
return true;
}
/**
* Subclass of BeanFactoryAdvisorRetrievalHelper that delegates to
* surrounding AbstractAdvisorAutoProxyCreator facilities.
*/
private class BeanFactoryAdvisorRetrieverAdapter extends BeanFactoryAdvisorRetriever {
public BeanFactoryAdvisorRetrieverAdapter(ConfigurableBeanFactory beanFactory) {
super(beanFactory);
}
@Override
protected boolean isEligibleBean(String beanName) {
return AbstractAdvisorAutoProxyCreator.this.isEligibleAdvisorBean(beanName);
}
}
}