ApplicationContextAware接口的作用

如果Bean类实现了ApplicationContextAware 接口，那么在加载Spring配置时，会自动调用ApplicationContextAware 接口中的

public void setApplicationContext(ApplicationContext applicationContext) throws BeansException

方法，获得ApplicationContext对象。

package com.whl;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.annotation.Configuration;

@Configuration
public class SpringUtil implements ApplicationContextAware {

	private static ApplicationContext applicationContext = null;

	@Override
	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
		if (SpringUtil.applicationContext == null) {
			SpringUtil.applicationContext = applicationContext;
		}
	}

	//获取applicationContext
	public static ApplicationContext getApplicationContext() {
		return applicationContext;
	}

	//通过name获取 Bean.
	public static Object getBean(String name) {
		return getApplicationContext().getBean(name);
	}
	
	//通过class获取Bean.
	public static <T> T getBean(Class<T> clazz) {
		return getApplicationContext().getBean(clazz);
	}

	//通过name,以及Clazz返回指定的Bean
	public static <T> T getBean(String name, Class<T> clazz) {
		return getApplicationContext().getBean(name, clazz);
	}

}

通过ApplicationContext对象，按需操作applicationContext的方法和属性

转载于:https://my.oschina.net/u/3506422/blog/1541258