基于Xml方式Bean的配置-初始化方法和销毁方法

SpringBean的配置详解

• Bean的初始化和销毁方法配置
  • Bean在被实例化后，可以执行指定的初始化方法完成一些初始化的操作，Bean在销毁之前也可以执行指定的销毁方法完成一些操作，初始化方法名称和销毁方法名称通过

    •    <bean id="userService" name="aaa,bbb" class="com.example.Service.Impl.UserServiceImpl" init-method="init"destroy-method="destroy">

    • 指定的方法名于自己创建的方法名一致即可

      • package com.example.Service.Impl;import com.example.DAO.UserDAO;
        import com.example.Service.UserService;public class UserServiceImpl implements UserService {public void init() {System.out.println("初始化方法");}public void destroy() {System.out.println("销毁方法");}public UserServiceImpl() {System.out.println("UserServiceImpl实例化");}private UserDAO userDAO;public void setUserDAO(UserDAO userDAO) {}
        }
        

    • 测试类

      • package com.example.Test;import org.springframework.context.ApplicationContext;
        import org.springframework.context.support.ClassPathXmlApplicationContext;public class TestApplicationContext {public static void main(String[] args) {ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("application.xml");Object userService1 = context.getBean("userService");System.out.println(userService1);context.close();}
        }
        

    • 运行结果如下

      • 

拓展 

• 我们还可以通过实现InitializingBean接口，完成bean的初始化操作

  • package com.example.Service.Impl;import com.example.DAO.UserDAO;
    import com.example.Service.UserService;
    import org.springframework.beans.factory.InitializingBean;public class UserServiceImpl implements UserService, InitializingBean {public void init() {System.out.println("初始化方法");}public void destroy() {System.out.println("销毁方法");}public UserServiceImpl() {System.out.println("UserServiceImpl实例化");}private UserDAO userDAO;public void setUserDAO(UserDAO userDAO) {}// todo 执行时机早于init-method方法@Overridepublic void afterPropertiesSet() throws Exception {System.out.println("InitializingBean.....");}
    }
    

  • 测试类运行结果如下

    •