ITLife365 生活 互动学习空间 - 互动学习空间

在我所做 的项目中用到session的地方


1。用户的登录/退出
2。购物车
在jsp+servelt+javabean的mvc的开发模式下的应用：只粘贴servlet代码了：

登录：

Java代码

if (user != null) {
HttpSession session = request.getSession(true);
session.setAttribute("user", user);

ShopCart cart = new ShopCart();
session.setAttribute("cart", cart);
response.sendRedirect("../product/products1.jsp");

}else {
request.setAttribute("msg", "此用户不存在");
this.getServletContext().getRequestDispatcher("/index.jsp").forward(request, response);
}

用户退出：

 

Java代码

1. HttpSession session=request.getSession( false );   
2. session.removeAttribute( "cart" );   
3. session.removeAttribute( "user" );   
4. session.invalidate();   
5. response.sendRedirect( "../index.jsp" );  

HttpSession session=request.getSession(false);
session.removeAttribute("cart");
session.removeAttribute("user");
session.invalidate();
response.sendRedirect("../index.jsp");

购物车：

 

Java代码

1.   
2. public   void  doGet(HttpServletRequest request, HttpServletResponse response)   
3.              throws  ServletException, IOException {   
4.            
5.         String option=request.getParameter( "option" );   
6.            
7.            
8.         System.out.println( "-------------" +option);   
9.          if (option!= null &&! "" .equals(option)){   
10.             HttpSession session=request.getSession( false );   
11.             ShopCart cart=(ShopCart)session.getAttribute( "cart" );   
12.                
13.              if (cart== null ){   
14.                 cart= new  ShopCart();   
15.                 session.setAttribute( "cart" , cart);   
16.             }   
17.              String pid=request.getParameter( "pid" );   
18.                          int  id=Integer.parseInt(pid);   
19.                
20.                         ProductDAO pdao= new  ProductDAOimpl();   
21.              if ( "add" .equals(option)){   
22.                 Product product=pdao.getProductById(id);   
23.                 cart.addProduct(product);   
24.                  //this.getServletContext().getRequestDispatcher("/servlet/ProductServlet?option=userfind").forward(request, response);   
25.                    
26.                    
27.                    
28.             } else   if ( "delet" .equals(option)){   
29.                    
30.                 cart.deletProduct(id);   
31.                  this .getServletContext().getRequestDispatcher( "/product/cartshowyk.jsp" ).forward(request, response);   
32.                    
33.                    
34.                    
35.                    
36.            
37.                    
38.                    
39.             } else   if ( "update" .equals(option)){   
40.                 String number2=request.getParameter( "number2" );   
41.                  int  number=Integer.parseInt(number2);   
42.                 cart.updateProductNumber(id, number);   
43.                  this .getServletContext().getRequestDispatcher( "/product/cartshowyk.jsp" ).forward(request, response);   
44.                    
45.                    
46.                    
47.                    
48.             }   
49.         }   
50.   
51.     }  

public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		String option=request.getParameter("option");
		
		
		System.out.println("-------------"+option);
		if(option!=null&&!"".equals(option)){
			HttpSession session=request.getSession(false);
			ShopCart cart=(ShopCart)session.getAttribute("cart");
			
			if(cart==null){
				cart=new ShopCart();
				session.setAttribute("cart", cart);
			}
			 String pid=request.getParameter("pid");
						int id=Integer.parseInt(pid);
			
						ProductDAO pdao=new ProductDAOimpl();
			if("add".equals(option)){
				Product product=pdao.getProductById(id);
				cart.addProduct(product);
				//this.getServletContext().getRequestDispatcher("/servlet/ProductServlet?option=userfind").forward(request, response);
				
				
				
			}else if("delet".equals(option)){
				
				cart.deletProduct(id);
				this.getServletContext().getRequestDispatcher("/product/cartshowyk.jsp").forward(request, response);
				
				
				
				
		
				
				
			}else if("update".equals(option)){
				String number2=request.getParameter("number2");
				int number=Integer.parseInt(number2);
				cart.updateProductNumber(id, number);
				this.getServletContext().getRequestDispatcher("/product/cartshowyk.jsp").forward(request, response);
				
				
				
				
			}
		}

	}

----------------------------------------------------------------------下面只貼 在struts2 中获取 session，reuqest，response的方法：

1.
非IoC(Spring中的控制反转)方式：

 

Java代码

1.   
2. 直接使用ServletActionContext类的getRequest、getResponse方法来获得HttpServletRequest、HttpServletResponse对象。代码如下：   
3.       
4.  HttpServletRequest request=ServletActionContext.getRequest();   
5.  HttpServletResponse response = ServletActionContext.getResponse();   
6.   
7. Map session=ActionContext.getContext().getSession();  

直接使用ServletActionContext类的getRequest、getResponse方法来获得HttpServletRequest、HttpServletResponse对象。代码如下：
   
 HttpServletRequest request=ServletActionContext.getRequest();
 HttpServletResponse response = ServletActionContext.getResponse();

Map session=ActionContext.getContext().getSession();

2.IoC方式：
 

Java代码

1. public   class  BaseAction  extends  ActionSupport  implements  SessionAware, ServletRequestAware, ServletResponseAware {      
2.      
3.       
4.           
5.     ActionContext context = ActionContext.getContext();      
6.     HttpServletRequest request;      
7.     HttpServletResponse response;      
8.     SessionMap session;      
9. public   void  setSession(Map map) {      
10.          this .session = (SessionMap) map;      
11.     }      
12.      public   void  setServletRequest(HttpServletRequest request) {      
13.          this .request = request;      
14.     }      
15.      public   void  setServletResponse(HttpServletResponse response) {      
16.          this .response = response;      
17.     }      
18.           
19. }    

public class BaseAction extends ActionSupport implements SessionAware, ServletRequestAware, ServletResponseAware {   
  
   
       
    ActionContext context = ActionContext.getContext();   
    HttpServletRequest request;   
    HttpServletResponse response;   
    SessionMap session;   
public void setSession(Map map) {   
        this.session = (SessionMap) map;   
    }   
    public void setServletRequest(HttpServletRequest request) {   
        this.request = request;   
    }   
    public void setServletResponse(HttpServletResponse response) {   
        this.response = response;   
    }   
       
}  

三。项目中session的用法


1.session的创建

Map session = ActionContext.getContext().getSession();
session.put("usr", usr);
2.通过session获取值
在jsp页面中：

<s:property value="#session.usr.username"/>


3.session的销毁
Map session = ActionContext.getContext().getSession();
session.remove("usr");
session.clear();

4.然后在jsp中取值：
<s:property value="#session.user.username"/> 
 原文地址：http://kaixuan489577823.javaeye.com/blog/665404