ApplicationContextAware介面和Aware介面
阿新 • • 發佈:2019-01-07
1.1ApplicationContextAware介面作用
1.2ApplicationContextAware介面原始碼
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介面作用
2.1Aware介面原始碼
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 { }