/*
* Copyright 2002-2008 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.beans.factory.wiring;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanCreationException;
import org.springframework.beans.factory.BeanCurrentlyInCreationException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* Convenient base class for configurers that can perform Dependency Injection
* on objects (however they may be created). Typically subclassed by AspectJ aspects.
*
* <p>Subclasses may also need a custom metadata resolution strategy, in the
* {@link BeanWiringInfoResolver} interface. The default implementation looks
* for a bean with the same name as the fully-qualified class name. (This is
* the default name of the bean in a Spring XML file if the '<code>id</code>'
* attribute is not used.)
* @author Rob Harrop
* @author Rod Johnson
* @author Juergen Hoeller
* @author Adrian Colyer
* @since 2.0
* @see #setBeanWiringInfoResolver
* @see ClassNameBeanWiringInfoResolver
*/
public class BeanConfigurerSupport implements BeanFactoryAware, InitializingBean, DisposableBean {
/** Logger available to subclasses */
protected final Log logger = LogFactory.getLog(getClass());
private volatile BeanWiringInfoResolver beanWiringInfoResolver;
private volatile ConfigurableListableBeanFactory beanFactory;
/**
* Set the {@link BeanWiringInfoResolver} to use.
* <p>The default behavior is to look for a bean with the same name as the class.
* As an alternative, consider using annotation-driven bean wiring.
* @see ClassNameBeanWiringInfoResolver
* @see org.springframework.beans.factory.annotation.AnnotationBeanWiringInfoResolver
*/
public void setBeanWiringInfoResolver(BeanWiringInfoResolver beanWiringInfoResolver) {
Assert.notNull(beanWiringInfoResolver, "BeanWiringInfoResolver must not be null");
this.beanWiringInfoResolver = beanWiringInfoResolver;
}
/**
* Set the {@link BeanFactory} in which this aspect must configure beans.
*/
public void setBeanFactory(BeanFactory beanFactory) {
if (!(beanFactory instanceof ConfigurableListableBeanFactory)) {
throw new IllegalArgumentException(
"Bean configurer aspect needs to run in a ConfigurableListableBeanFactory: " + beanFactory);
}
this.beanFactory = (ConfigurableListableBeanFactory) beanFactory;
if (this.beanWiringInfoResolver == null) {
this.beanWiringInfoResolver = createDefaultBeanWiringInfoResolver();
}
}
/**
* Create the default BeanWiringInfoResolver to be used if none was
* specified explicitly.
* <p>The default implementation builds a {@link ClassNameBeanWiringInfoResolver}.
* @return the default BeanWiringInfoResolver (never <code>null</code>)
*/
protected BeanWiringInfoResolver createDefaultBeanWiringInfoResolver() {
return new ClassNameBeanWiringInfoResolver();
}
/**
* Check that a {@link BeanFactory} has been set.
*/
public void afterPropertiesSet() {
Assert.notNull(this.beanFactory, "BeanFactory must be set");
}
/**
* Release references to the {@link BeanFactory} and
* {@link BeanWiringInfoResolver} when the container is destroyed.
*/
public void destroy() {
this.beanFactory = null;
this.beanWiringInfoResolver = null;
}
/**
* Configure the bean instance.
* <p>Subclasses can override this to provide custom configuration logic.
* Typically called by an aspect, for all bean instances matched by a
* pointcut.
* @param beanInstance the bean instance to configure (must <b>not</b> be <code>null</code>)
*/
public void configureBean(Object beanInstance) {
if (this.beanFactory == null) {
if (logger.isDebugEnabled()) {
logger.debug("BeanFactory has not been set on " + ClassUtils.getShortName(getClass()) + ": " +
"Make sure this configurer runs in a Spring container. Unable to configure bean of type [" +
ClassUtils.getDescriptiveType(beanInstance) + "]. Proceeding without injection.");
}
return;
}
BeanWiringInfo bwi = this.beanWiringInfoResolver.resolveWiringInfo(beanInstance);
if (bwi == null) {
// Skip the bean if no wiring info given.
return;
}
try {
if (bwi.indicatesAutowiring() ||
(bwi.isDefaultBeanName() && !this.beanFactory.containsBean(bwi.getBeanName()))) {
// Perform autowiring (also applying standard factory / post-processor callbacks).
this.beanFactory.autowireBeanProperties(beanInstance, bwi.getAutowireMode(), bwi.getDependencyCheck());
Object result = this.beanFactory.initializeBean(beanInstance, bwi.getBeanName());
checkExposedObject(result, beanInstance);
}
else {
// Perform explicit wiring based on the specified bean definition.
Object result = this.beanFactory.configureBean(beanInstance, bwi.getBeanName());
checkExposedObject(result, beanInstance);
}
}
catch (BeanCreationException ex) {
Throwable rootCause = ex.getMostSpecificCause();
if (rootCause instanceof BeanCurrentlyInCreationException) {
BeanCreationException bce = (BeanCreationException) rootCause;
if (this.beanFactory.isCurrentlyInCreation(bce.getBeanName())) {
String msg = ClassUtils.getShortName(getClass()) + " failed to create target bean '" +
bce.getBeanName() + "' while configuring object of type [" +
beanInstance.getClass().getName() + "] (probably due to a circular reference). " +
"Proceeding without injection.";
if (logger.isDebugEnabled()) {
logger.debug(msg, ex);
}
else if (logger.isInfoEnabled()) {
logger.info(msg);
}
return;
}
}
throw ex;
}
}
private void checkExposedObject(Object exposedObject, Object originalBeanInstance) {
if (exposedObject != originalBeanInstance) {
throw new IllegalStateException("Post-processor tried to replace bean instance of type [" +
originalBeanInstance.getClass().getName() + "] with (proxy) object of type [" +
exposedObject.getClass().getName() + "] - not supported for aspect-configured classes!");
}
}
}