Question

我创建了一个包含三个字段Usertype，Username和Password的Login页面。 Usertype有选择框（或选择标记），Username有textfield，Password也有textfield。登录每个字段必须正确。问题是我成功地能够验证用户名和密码但无法使用usertype，用户名和密码。我有login.java和index.jsp。

Login.java

package roseindia.net;

import java.io.*;

//import java.util.*;
import javax.servlet.*;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import java.sql.*;

/*** Servlet implementation class Login
***/
 @WebServlet(description = "Login Servlet", urlPatterns = { "/login" })
public class Login extends HttpServlet {
    private static final long serialVersionUID = 1L;

/**
 * @see HttpServlet#HttpServlet()
 */
public Login() {
    super();
    // TODO Auto-generated constructor stub
}

    /**
     * @see Servlet#init(ServletConfig)
     */
    public void init(ServletConfig config) throws ServletException {
        // TODO Auto-generated method stub
    }

    /**
         * @see HttpServlet#service(HttpServletRequest request, HttpServletResponse response)
         */
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        System.out.println("We are service method of servlet");

        /*
        String username="user";
        String password="root";
        */


        String un=request.getParameter("username");
        String pw=request.getParameter("password");
        String ut=request.getParameter("usertype");

        String msg=" ";

        Connection conn=null;
        String url="jdbc:mysql://localhost:3306/";
        String dbName="userlogindb";
        String driver="com.mysql.jdbc.Driver";
        String dbUserName="root";
        String dbPassword="root";

        try{
        Class.forName(driver).newInstance();
        conn = DriverManager.getConnection(url+dbName,dbUserName,dbPassword);
        String strQuery="select * from registerutable where username='" + un + "' and    password1='" + pw + "' and usertype='" + ut + "'";
        Statement st= conn.createStatement();
        ResultSet rs= st.executeQuery(strQuery);
        if(rs.next())
        {
            msg="Hello "    + un + "! Your login is successful";
            request.setAttribute("msg", msg);
            RequestDispatcher  req=request.getRequestDispatcher("/successful.jsp"); 
            req.forward(request, response);
        } else
        {
            msg="Hello "    + un + "! Your login failed";
            request.setAttribute("msg", msg);
            RequestDispatcher req=request.getRequestDispatcher("/failed.jsp"); 
            req.forward(request, response);
        }
        rs.close();
        st.close();
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

        /*
        if(un.equals(username) && pw.equals(password))
        {
           msg="Hello " + un + "! Your login is successful"; 
        }
        else
        {
           msg="Hello " + un + "! Your login failed"; 
        }
        */
        response.setContentType("text/html");
        PrintWriter out=response.getWriter();
        out.println("<font size='6' color=red>" + msg + "</font>");


    }

   }

的index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"   "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login Example</title>
</head>
<body>
<form name="loginform" action="login" method="post">
<div style="width:300px;margin:0 auto;">
<p>User Type: <select>
                <option value="employee">Employee</option>
                <option value="proj-coordinator">Project Co-ordinator</option>
                <option value="proj-manager">Project Manager</option>
                <option value="admin">Admin</option>
          </select>
</p>
<p>User Name: <input type="text" name="username"></p><br>
<p>Password:&nbsp;&nbsp;&nbsp;&nbsp;<input type="password" name="password"></p><br>
<center><input type="submit" value="Login"></center>
</div>
</form>
</body>
</html>

当我运行此程序并使用正确的值验证它时，它也显示登录失败/失败页面。请解决此问题

Answer 1

在jsp中更改您的选择类型，如下所示

  User Type: <select name="usertype">
                <option value="employee">Employee</option>
                <option value="proj-coordinator">Project Co-ordinator</option>
                <option value="proj-manager">Project Manager</option>
                <option value="admin">Admin</option>
          </select>

Answer 2

@Atiq：您上面提到的代码，似乎您没有在jsp中将name标记的<select>属性设置为usertype。尝试添加它，然后检查，它应该工作。

多用户登录验证在eclipse中使用servlet和jsp失败

2 个答案: