实例化bean的方式

一：装配Bean(xml)

	1、通过构造方法实例化
		```
		<bean id="userService" class="cn.lh.service.UserServiceImpl"></bean>
		
	ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
    UserService userService = (UserService) context.getBean("userService");
		```
	2、通过静态工厂方法进行实例化

 <bean id="userService" class="com.lh.service.UserSereviceFactory"  factory-method="createUserService"></bean>
    
    UserService userService = UserSereviceFactory.createUserService();
    UserService userService = (UserService) context.getBean("userService");
    userService.add();

	3、使用实例工厂放大进行实例化

创建工厂
   /UserSereviceFactory factory = new UserSereviceFactory();
    UserService userService = factory.createUserService();

    UserService userService3 = (IUserService) context.getBean("userService");
    userService.add();

在配置bean的时候有一个scope属性：

 <bean id="userService" class="cn.lh.service.UserServiceImpl" scope="prototype"></bean>   
 多例模式：每次获得的bean都是新的
 <bean id="userService" class="cn.lh.service.UserServiceImpl" scope="singleton"></bean>
 单例模式：每次获得的bean都是同一个对象