Spring中使用两种Aware接口自定义获取bean
本文内容纲要:Spring中使用两种Aware接口自定义获取bean
在使用spring编程时,常常会遇到想根据bean的名称来获取相应的bean对象,这时候,就可以通过实现BeanFactoryAware来满足需求,代码很简单:
@Servicepublic class BeanFactoryHelper implements BeanFactoryAware {
private static BeanFactory beanFactory;
@Override
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
this.beanFactory = beanFactory;
}
public static Object getBean(String beanName){
if(beanFactory == null){
throw new NullPointerException("BeanFactory is null!");
}
return beanFactory.getBean(beanName);
}
}
还有一种方式是实现ApplicationContextAware接口,代码也很简单:
@Servicepublic class ApplicationContextHelper implements ApplicationContextAware {
private static ApplicationContext applicationContext;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = applicationContext;
}
public static Object getBean(String beanName){
if(applicationContext == null){
throw new NullPointerException("ApplicationContext is null!");
}
return applicationContext.getBean(beanName);
}
}
上面两种方法,只有容器启动的时候,才会把BeanFactory和ApplicationContext注入到自定义的helper类中,如果在本地junit测试的时候,如果需要根据bean的名称获取bean对象,则可以通过ClassPathXmlApplicationContext来获取一个ApplicationContext,代码如下:
@Test public void test() throws SQLException {
//通过从classpath中加载spring-mybatis.xml实现bean的获取
ApplicationContext context = new ClassPathXmlApplicationContext("spring-mybatis.xml");
IUserService userService = (IUserService) context.getBean("userService");
User user = new User();
user.setName("test");
user.setAge(20);
userService.addUser(user);
}
本文内容总结:Spring中使用两种Aware接口自定义获取bean
原文链接:https://www.cnblogs.com/handsomeye/p/6277510.html
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