SSM1.3【Spring：Spring相关API】

 

 

//        ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
        ApplicationContext app = new FileSystemXmlApplicationContext("D:\\Workspace-java\\idea\\Workspaces\\itheima-javaweb\\SSM1_spring_ioc\\src\\main\\resources\\applicationContext.xml");
        UserService userService = (UserService)app.getBean("userService");
        userService.save();

 

 

 

ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
//        ApplicationContext app = new FileSystemXmlApplicationContext("D:\\Workspace-java\\idea\\Workspaces\\itheima-javaweb\\SSM1_spring_ioc\\src\\main\\resources\\applicationContext.xml");

//        Object userService = app.getBean("userService");
//        UserService userService = (UserService)app.getBean("userService");

        UserService userService = app.getBean(UserService.class);
        //仅适用于配置文件中只有一个UserServiceImpl时，多个bean虽然id不同，但class一致时，这种方式会报错，比如如下配置

        userService.save();

<bean id="userService" class="com.haifei.service.impl.UserServiceImpl">
        <property name="userDao" ref="userDao"></property>
    </bean>

<bean id="userService2" class="com.haifei.service.impl.UserServiceImpl">
        <property name="userDao" ref="userDao"></property>
    </bean>