浅谈Spring Bean的作用域之间有什么区别

@Component  
@Scope( "session")  
public class SessionObj {  
  
}  
@Component  
@Scope( "request")  
public class RequestObj {  
  
}  
@Component  
@Scope( "prototype")  
public class PrototypeObj {  
  
}  
@Component  
@Scope( "singleton")  
public class SingletonObj {  
  
}  

@Controller  
public class IndexController implements ApplicationContextAware {  
  
    private RequestObj RequestObj;  
  
    private SessionObj SessionObj;  
  
    private PrototypeObj PrototypeObj;  
  
    private SingletonObj SingletonObj;  
  
    private ApplicationContext applicationContext;  
  
    @RequestMapping("/")  
    @ResponseBody  
    public String index() {  
        print();  
        return "Welcome";  
    }  
  
    public void print() {  
        System.out.println("first  time singleton is :" + getSingletonObj());  
        System.out.println("second time singleton is :" + getSingletonObj());  
  
        System.out.println("first  time prototype is :" + getPrototypeObj());  
        System.out.println("second time prototype is :" + getPrototypeObj());  
  
        System.out.println("first  time request is :" + getRequestObj());  
        System.out.println("second time request is :" + getRequestObj());  
  
        System.out.println("first  time session is :" + getSessionObj());  
        System.out.println("second time session is :" + getSessionObj());  
    }  
  
    @Override  
    public void setApplicationContext(ApplicationContext applicationContext)  
            throws BeansException {  
        this.applicationContext = applicationContext;  
    }  
  
    public RequestObj getRequestObj() {  
        return applicationContext.getBean(RequestObj.class);  
    }  
  
    public void setRequestObj(RequestObj requestObj) {  
        RequestObj = requestObj;  
    }  
  
    public SessionObj getSessionObj() {  
        return applicationContext.getBean(SessionObj.class);  
    }  
  
    public void setSessionObj(SessionObj sessionObj) {  
        SessionObj = sessionObj;  
    }  
  
    public PrototypeObj getPrototypeObj() {  
        return applicationContext.getBean(PrototypeObj.class);  
    }  
  
    public void setPrototypeObj(PrototypeObj prototypeObj) {  
        PrototypeObj = prototypeObj;  
    }  
  
    public SingletonObj getSingletonObj() {  
        return applicationContext.getBean(SingletonObj.class);  
    }  
  
    public void setSingletonObj(SingletonObj singletonObj) {  
        SingletonObj = singletonObj;  
    }  
  
}  
 
 

//使用chrome第一次打印数据：  
first  time singleton is :com.fb.po.SingletonObj@1e3223e  
second time singleton is :com.fb.po.SingletonObj@1e3223e  
first  time prototype is :com.fb.po.PrototypeObj@3e683f  
second time prototype is :com.fb.po.PrototypeObj@12e18d7  
first  time request is :com.fb.po.RequestObj@1d45706  
second time request is :com.fb.po.RequestObj@1d45706  
first  time session is :com.fb.po.SessionObj@9a6b2e  
second time session is :com.fb.po.SessionObj@9a6b2e  
  
  
  
//使用chrome打印第二次数据  
first  time singleton is :com.fb.po.SingletonObj@1e3223e  
second time singleton is :com.fb.po.SingletonObj@1e3223e  
first  time prototype is :com.fb.po.PrototypeObj@122e5be  
second time prototype is :com.fb.po.PrototypeObj@192add  
first  time request is :com.fb.po.RequestObj@4d1b6c  
second time request is :com.fb.po.RequestObj@4d1b6c  
first  time session is :com.fb.po.SessionObj@9a6b2e  
second time session is :com.fb.po.SessionObj@9a6b2e  
  
  
  
//使用IE打印第三次数据  
first  time singleton is :com.fb.po.SingletonObj@1e3223e  
second time singleton is :com.fb.po.SingletonObj@1e3223e  
first  time prototype is :com.fb.po.PrototypeObj@10f1ecb  
second time prototype is :com.fb.po.PrototypeObj@1aeb990  
first  time request is :com.fb.po.RequestObj@18a1e7  
second time request is :com.fb.po.RequestObj@18a1e7  
first  time session is :com.fb.po.SessionObj@12d5c55  
second time session is :com.fb.po.SessionObj@12d5c55  
 

<listener>   
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>   
</listener>