ApplicationContextAware接口和Aware接口

1.1ApplicationContextAware接口作用

1.2ApplicationContextAware接口源码

package org.springframework.context;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.Aware;

/**
 * Interface to be implemented by any object that wishes to be notified
 * of the {@link ApplicationContext} that it runs in.
 *
 * <p>Implementing this interface makes sense for example when an object
 * requires access to a set of collaborating beans. Note that configuration
 * via bean references is preferable to implementing this interface just
 * for bean lookup purposes.
 *
 * <p>This interface can also be implemented if an object needs access to file
 * resources, i.e. wants to call {@code getResource}, wants to publish
 * an application event, or requires access to the MessageSource. However,
 * it is preferable to implement the more specific {@link ResourceLoaderAware},
 * {@link ApplicationEventPublisherAware} or {@link MessageSourceAware} interface
 * in such a specific scenario.
 *
 * <p>Note that file resource dependencies can also be exposed as bean properties
 * of type {@link org.springframework.core.io.Resource}, populated via Strings
 * with automatic type conversion by the bean factory. This removes the need
 * for implementing any callback interface just for the purpose of accessing
 * a specific file resource.
 *
 * <p>{@link org.springframework.context.support.ApplicationObjectSupport} is a
 * convenience base class for application objects, implementing this interface.
 *
 * <p>For a list of all bean lifecycle methods, see the
 * {@link org.springframework.beans.factory.BeanFactory BeanFactory javadocs}.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Chris Beams
 * @see ResourceLoaderAware
 * @see ApplicationEventPublisherAware
 * @see MessageSourceAware
 * @see org.springframework.context.support.ApplicationObjectSupport
 * @see org.springframework.beans.factory.BeanFactoryAware
 */
public interface ApplicationContextAware extends Aware {

	/**
	 * Set the ApplicationContext that this object runs in.
	 * Normally this call will be used to initialize the object.
	 * <p>Invoked after population of normal bean properties but before an init callback such
	 * as {@link org.springframework.beans.factory.InitializingBean#afterPropertiesSet()}
	 * or a custom init-method. Invoked after {@link ResourceLoaderAware#setResourceLoader},
	 * {@link ApplicationEventPublisherAware#setApplicationEventPublisher} and
	 * {@link MessageSourceAware}, if applicable.
	 * @param applicationContext the ApplicationContext object to be used by this object
	 * @throws ApplicationContextException in case of context initialization errors
	 * @throws BeansException if thrown by application context methods
	 * @see org.springframework.beans.factory.BeanInitializationException
	 */
	void setApplicationContext(ApplicationContext applicationContext) throws BeansException;

}

2.1Aware接口作用

2.1Aware接口源码

package org.springframework.beans.factory;

/**
 * Marker superinterface indicating that a bean is eligible to be
 * notified by the Spring container of a particular framework object
 * through a callback-style method. Actual method signature is
 * determined by individual subinterfaces, but should typically
 * consist of just one void-returning method that accepts a single
 * argument.
 *
 * <p>Note that merely implementing {@link Aware} provides no default
 * functionality. Rather, processing must be done explicitly, for example
 * in a {@link org.springframework.beans.factory.config.BeanPostProcessor BeanPostProcessor}.
 * Refer to {@link org.springframework.context.support.ApplicationContextAwareProcessor}
 * and {@link org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory}
 * for examples of processing {@code *Aware} interface callbacks.
 *
 * @author Chris Beams
 * @since 3.1
 */
public interface Aware {

}