/*
* Copyright 2002-2010 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.support;
import java.io.IOException;
import java.io.ObjectInputStream;
import org.aopalliance.aop.Advice;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.util.Assert;
/**
* Abstract BeanFactory-based PointcutAdvisor that allows for any Advice
* to be configured as reference to an Advice bean in a BeanFactory.
*
* <p>Specifying the name of an advice bean instead of the advice object itself
* (if running within a BeanFactory) increases loose coupling at initialization time,
* in order to not initialize the advice object until the pointcut actually matches.
*
* @author Juergen Hoeller
* @since 2.0.2
* @see #setAdviceBeanName
* @see DefaultBeanFactoryPointcutAdvisor
*/
public abstract class AbstractBeanFactoryPointcutAdvisor extends AbstractPointcutAdvisor implements BeanFactoryAware {
private String adviceBeanName;
private BeanFactory beanFactory;
private transient Advice advice;
private transient volatile Object adviceMonitor = new Object();
/**
* Specify the name of the advice bean that this advisor should refer to.
* <p>An instance of the specified bean will be obtained on first access
* of this advisor's advice. This advisor will only ever obtain at most one
* single instance of the advice bean, caching the instance for the lifetime
* of the advisor.
* @see #getAdvice()
*/
public void setAdviceBeanName(String adviceBeanName) {
this.adviceBeanName = adviceBeanName;
}
/**
* Return the name of the advice bean that this advisor refers to, if any.
*/
public String getAdviceBeanName() {
return this.adviceBeanName;
}
public void setBeanFactory(BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
public Advice getAdvice() {
synchronized (this.adviceMonitor) {
if (this.advice == null && this.adviceBeanName != null) {
Assert.state(this.beanFactory != null, "BeanFactory must be set to resolve 'adviceBeanName'");
this.advice = this.beanFactory.getBean(this.adviceBeanName, Advice.class);
}
return this.advice;
}
}
@Override
public String toString() {
return getClass().getName() + ": advice bean '" + getAdviceBeanName() + "'";
}
//---------------------------------------------------------------------
// Serialization support
//---------------------------------------------------------------------
private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
// Rely on default serialization, just initialize state after deserialization.
ois.defaultReadObject();
// Initialize transient fields.
this.adviceMonitor = new Object();
}
}
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