HTTP servlet和jsp 404

Z时代
2024-01-10
分类：问答

我有这种疾病的时候我编程这样的：HTTP servlet和jsp 404

HTTP状态404 -/IT/UserServlet
类型报告“
状态
留言/ IT/UserServlet
描述所请求的资源不可用。
的Apache Tomcat/8.0.27

这是我的代码： register.jsp

<head> 
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 
     <title>Register Page</title> 
     <script src="https://s.codepen.io/assets/libs/modernizr.js" type="text/javascript"></script> 
     <link rel="stylesheet" href="css/register_style.css"> 
     <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript"></script> 
     <script type="text/javascript"> 
      $(document).ready(function() { 
       var x_timer; 
       $("#username").keyup(function (e) { 
        clearTimeout(x_timer); 
        var user_name = $(this).val(); 
        x_timer = setTimeout(function() { 
         check_username_ajax(user_name); 
        }, 1000); 
       }); 
       function check_username_ajax(username) { 
        $("#user-result").html('<img src="img/ajax-loader.gif" />'); 
        $.post('CheckUserNameServlet', {'username': username}, function (data) { 
         $("#user-result").html(data); 
        }); 
       } 
      }); 
     </script> 
    </head> 
    <body> 
     <form action="UserServlet" method="POST"> 
      <h1>Sign up</h1><br/> 
      <span class="input"></span> 
      <input type="text" name="name" id = "name" placeholder="Full name" autofocus autocomplete="off" /> 
      <span class="input" ></span> 
      <input type="text" name="username" id="username" placeholder="username" /> 
      <span id = "user-result"></span> 
      <span id="passwordMeter"></span> 
      <input type="password" name="password" id="password" placeholder="Password" title="Password min 8 characters. At least one UPPERCASE and one lowercase letter" required pattern="(?=^.{8,}$)(?=.*[a-z])(?=.*[A-Z])(?!.*\s).*$"/> 
      <input type="hidden" value="insert" name="command"> 
      <button type="submit" value="Sign Up" title="Submit form" class="icon-arrow-right"><span>Sign up</span></button> 
     </form>     
    </body>

这是sevlet：

public class UserServlet extends HttpServlet { 
    UserDAO userDao = new UserDAO(); 
    @Override 
    protected void doPost(HttpServletRequest request, HttpServletResponse response) 
      throws ServletException, IOException { 
     //processRequest(request, response); 
     String command = request.getParameter("command"); 
     String url=""; 
     switch(command){ 
      case"insert": 
       User user = new User(); 
       user.setUserId(new Date().getTime()); 
       user.setName(request.getParameter("name")); 
       user.setUserName(request.getParameter("username")); 
       user.setPassword(request.getParameter("password")); 
       user.setCreateTime(Date.from(Instant.now())); 
       user.setUpdateTime(Date.from(Instant.now())); 
       userDao.InsertUser(user); 
       HttpSession session = request.getSession(); 
       session.setAttribute("user", user); 
       url = "index.jsp"; 
       break;    
     } 
     RequestDispatcher rd = getServletContext().getRequestDispatcher(url); 
     rd.forward(request, response); 
    } 
}

这是UseDAO：

public boolean InsertUser(User u) { 
     Connection conn = Connect.getConnecttion(); 
     String insert_user = "INSERT INTO user(name, user_name, password, role, create_time, update_time) values(?,?,?,?,?,?)"; 
     try { 
      PreparedStatement ps = conn.prepareStatement(insert_user); 
      ps.setString(1, u.getName()); 
      ps.setString(2, u.getUserName()); 
      ps.setString(3, u.getPassword()); 
      ps.setInt(4, 4); 
      ps.setDate(5, Date.valueOf(LocalDate.now())); 
      ps.setDate(6, Date.valueOf(LocalDate.now())); 
      ps.executeUpdate(); 
      return true; 
     } catch (SQLException ex) { 
      Logger.getLogger(UserDAO.class.getName()).log(Level.SEVERE, null, ex); 
     } 
     return false; 
    }

我的web.xml：

<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> 
    <servlet> 
     <servlet-name>LoginServlet</servlet-name> 
     <servlet-class>Controller.UserServlet</servlet-class> 
    </servlet> 
    <servlet> 
     <servlet-name>CheckUserNameServlet</servlet-name> 
     <servlet-class>Controller.CheckUserNameServlet</servlet-class> 
    </servlet> 
    <servlet-mapping> 
     <servlet-name>LoginServlet</servlet-name> 
     <url-pattern>/LoginServlet</url-pattern> 
    </servlet-mapping> 
    <servlet-mapping> 
     <servlet-name>CheckUserNameServlet</servlet-name> 
     <url-pattern>/CheckUserNameServlet</url-pattern> 
    </servlet-mapping> 
    <session-config> 
     <session-timeout> 
      30 
     </session-timeout> 
    </session-config> 
</web-app>