需求:spring框架的使用让开发简化,但是有时候我们一般的类需要使用已经注入到spring容器中的Dao或者Service时会报空指针异常;那么应该如何去调用呢?
1. 创建一个工具类去获取Bean,该类实现ApplicationContextAware接口
/**
* @author :maple
* @description:用于获取Spring容器中的Bean给普通类使用
* @date :Created in 2020/7/27 8:48
*/
@Component
public class SpringContextUtilService implements ApplicationContextAware {
private static ApplicationContext applicationContext = null;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
SpringContextUtilService.applicationContext = applicationContext;
}
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
public static Object getBean(String beanName) {
return applicationContext.getBean(beanName);
}
public static Object getBean(Class c) {
return applicationContext.getBean(c);
}