Web resource sharing

1、Request Implement request forwarding （ And the following Response Implement redirection distinguish ）

Request to forward resource sharing data ： Use Request object

void setAttribute（String name,Object o） Store data to request domain

Object getAttribute（String name） according to key Get value

void removeAttribute（Sting name） according to key, Delete the key-value pair

Case study web-demo01 

2、Response Implement redirection

response.sendRedirect("/web-demo01/resp02");

Case study web-demo01 

3、Cookie

 4、Session

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1 brand-demo The increased Delete It should all be used request Of

request.getRequestDispatcher("/selectAllServlet").forward(request,response);

2 brand-demo The query uses   Just save the data

  //         Package to request domain 
        request.setAttribute("brand",brand);
//         forward 
        request.getRequestDispatcher("update.jsp").forward(request,response);

3 brand-demo The login page of is

Landing successful     Session Resource sharing

//            session Shared resources 
            HttpSession session = request.getSession();
            session.setAttribute("user",user);
//           Implement redirection 
            response.sendRedirect("/brand-demo/selectAllServlet");

  I think of myself

//            request.setAttribute("login_name", user.getUsername());
//            request.getRequestDispatcher("/selectAllServlet").forward(request, response);

Login failed   It's using

//             Store information to request Domain 
            request.setAttribute("login_msg", " Wrong user name or password ");
//             forward 
            request.getRequestDispatcher("/login.jsp").forward(request, response);

I think of myself

//            HttpSession session = request.getSession();
//            session.setAttribute("login_msg"," Wrong user name or password ");
//            response.sendRedirect("/brand-demo/login.jsp");

4 brand-demo The login page verification code of is Cookie

// The user checked remember user 
Cookie c_username = new Cookie("username", username);
Cookie c_password = new Cookie("password", password);
// Remember the time 
c_username.setMaxAge(60*60*24*7);
c_password.setMaxAge(60*60*24*7);
// send out Cookie
response.addCookie(c_username);
response.addCookie(c_password);