Bean Scopes

Bean Scopes

官方文档

Scope	Description
singleton	(Default) Scopes a single bean definition to a single object instance for each Spring IoC container.
prototype	Scopes a single bean definition to any number of object instances.
request	Scopes a single bean definition to the lifecycle of a single HTTP request. That is, each HTTP request has its own instance of a bean created off the back of a single bean definition. Only valid in the context of a web-aware Spring .ApplicationContext
session	Scopes a single bean definition to the lifecycle of an HTTP . Only valid in the context of a web-aware Spring .Session``ApplicationContext
application	Scopes a single bean definition to the lifecycle of a . Only valid in the context of a web-aware Spring .ServletContext``ApplicationContext
websocket	Scopes a single bean definition to the lifecycle of a . Only valid in the context of a web-aware Spring .WebSocket``ApplicationContext

1.单例模式 （默认机制是单例）

代码实例（用的之前的beans.xml文件）

 com.wjj.pojo.Student student =(Student) context.getBean("student");
 com.wjj.pojo.Student student2 =(Student) context.getBean("student");
 System.out.println(student.hashCode());
 System.out.println(student2.hashCode());
 System.out.println(student.equals(student2));

2.圆形模式 (xml文件改动)

<bean id="student" class="com.wjj.pojo.Student" scope="prototype">