1. 概念

ApplicationContext是什么？

简单来说就是Spring中的容器，可以用来获取容器中的各种bean组件，注册监听事件，加载资源文件等功能

2. 获取ApplicationContext的方式

2.1. 创建工具类

通过此工具类，可以方便的获取bean组件, 获取配置信息等

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;public class ApplicationContextUtil {private static ApplicationContext applicationContext = null;private ApplicationContextUtil() {}public static void setApplicationContext(ApplicationContext applicationContext) throws BeansException {if (ApplicationContextUtil.applicationContext == null) {ApplicationContextUtil.applicationContext = applicationContext;}}/*** 获取applicationContext** @return*/public static ApplicationContext getApplicationContext() {return applicationContext;}/*** 通过name获取 Bean.** @param name* @return*/public static Object getBean(String name) {return getApplicationContext().getBean(name);}/*** 通过class获取Bean.** @param clazz* @param <T>* @return*/public static <T> T getBean(Class<T> clazz) {return getApplicationContext().getBean(clazz);}/*** 通过name,以及Clazz返回指定的Bean** @param name* @param clazz* @param <T>* @return*/public static <T> T getBean(String name, Class<T> clazz) {return getApplicationContext().getBean(name, clazz);}}

2.2 在main方法设置

@SpringBootApplication
public class SpiderApplication {public static void main(String[] args) {ConfigurableApplicationContext run = SpringApplication.run(SpiderApplication.class, args);ApplicationContextUtil.setApplicationContext(run);}}

3. 获取 beanFactory 的方式

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;public class BeanFactoryUtil implements BeanFactoryPostProcessor {private static BeanFactory beanFactory;@Overridepublic void postProcessBeanFactory(ConfigurableListableBeanFactory configurableListableBeanFactory) throws BeansException {init(configurableListableBeanFactory);}private static void init(BeanFactory factory) {beanFactory = factory;}public static BeanFactory getBeanFactory() {return beanFactory;}/*** 通过name获取 Bean.** @param name* @return*/public static Object getBean(String name) {return getBeanFactory().getBean(name);}/*** 通过class获取Bean.** @param clazz* @param <T>* @return*/public static <T> T getBean(Class<T> clazz) {return getBeanFactory().getBean(clazz);}/*** 通过name,以及Clazz返回指定的Bean** @param name* @param clazz* @param <T>* @return*/public static <T> T getBean(String name, Class<T> clazz) {return getBeanFactory().getBean(name, clazz);}}

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