验证用户后根据用户角色重定向页面

Question

我一直在尝试将已登录系统的用户在检查他们的电子邮件和密码后重定向到他们各自的页面。但我不确定编码背后的逻辑，当我尝试它时，它只是用 else 语句响应。我已经尝试验证电子邮件和密码并且工作正常并重定向到正确的页面，但是当我添加用户类型条件时它不起作用

我试过包含嵌套的 if 语句，但我不确定它的逻辑，它总是执行 else 语句。

loginControllerServlet.java

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


        String email=request.getParameter("email");
        String password=request.getParameter("pwrd");

        User theUser=loginDbUtil.gettype(email);

        if(loginDbUtil.check(email, password))
        {       
            String p="pharmacist";

            if(theUser.getType()==p)
            {
//              HttpSession session=request.getSession();
//                  session.setAttribute("email", email);
                    response.sendRedirect("medicine.jsp");
            }
            else
            {
                response.sendRedirect("index.jsp");
            }




    }else
    {
        response.sendRedirect("index.jsp");
    }

    }
}

loginDbUtil.java

public boolean check(String email,String password)
    {
        Connection myConn=null;
        PreparedStatement myStmt=null;
        ResultSet rs=null;

        try
        {
            //get db connection
            myConn=dataSource.getConnection();


            //sql statemtn
            String sql="select email,pass from usertab where email=? and pass=? ";


            myStmt=myConn.prepareStatement(sql);

            //set the param values for user
            myStmt.setString(1, email);
            myStmt.setString(2, password);

            rs=myStmt.executeQuery();

            if(rs.next())
            {
                return true;  
            }



        }catch(Exception e)
        {
            e.printStackTrace();
        }



        return false;
    }




    public User gettype(String email) {

        User type=null;

        Connection myConn=null;
        PreparedStatement myStmt=null;
        ResultSet rs=null;

        try
        {
            //get db connection
            myConn=dataSource.getConnection();


            //sql statemtn
            String sql="select type from usertab where email=?  ";


            myStmt=myConn.prepareStatement(sql);

            //set the param values for user
            myStmt.setString(1, email);

            rs=myStmt.executeQuery();

            if(rs.next())
            {
                String t=rs.getString("type");



            type =new User(t);

            }



        }catch(Exception e)
        {
            e.printStackTrace();
        }

        return type;

    }

}

我想要的是在检查电子邮件和密码之后，接下来检查用户数据类型并将他们重定向到正确的页面

Answer 1

按照你的逻辑，我觉得首先你应该把属性类型写成int，这样的类型出现Pharmacist和pharmacist的几率会比较小。

然后与数据库通信检查是否正确，但我认为您的 getType 方法不一样，这就是我建议您的方法：

第 1 步：创建一个 bean（对象）用户，就像您所做的那样，放置 getter 和 setter，并放置一个将所有属性作为参数的构造函数。

示例：

class User {
   
   private int id;
   private String mail;
   private String password;
   private int type;

   public User() {
   }

   public User(int id, String mail, String password, int type) {
      this.id = id;
      this.mail = mail;
      this.password = password;
      this.type = type;
   }
   
   // Getters and setters
}

然后你查邮件会return直接一个用户对象，所以你应该

class userDB {

   public User login(String mail, String password) {

      User user = new User();
      String query = "select * from user where mail = ? and password = ?";

      try {

         PreparedStatement prep = conn.prepareStatement(query);

         prep.setString(1,mail);
         prep.setString(2,password);

         ResultSet res = res.executeQuery();

         if(res.first) {

            user = new User(res.getInt("id"),res.getString("mail"),res.getString("password"),res.getInt("type"));
            return user;
         } else {
            
            return null;
      
         }

      } catch (Exception e) {

        e.printStackTrace();
        return null;
 
      }
   }
}

然后在你的 Servlet 中你可以这样写：

class Login extends HttpServlet {

   public void doGet(HttpServletRequest request, HttpServletResponse respons) throws ServletException, IOException {         
    
         this.getServletContext().getRequestDispatcher(your_jsp_relative_path).forward(request, respons);
        
    }

    public void doPost(HttpServletRequest request, HttpServletResponse respons) throws ServletException, IOException {       
    
        String mail = (String) request.getParameter("mail');
        String password = (String) request.getParameter("mail');

        User user = new UserDB().login(mail, password);

        if(user != null){

           int type = user.getType();

           switch(type){

              case 0 :
                   respons.sendRedirect("type_0_page");
              break;
              case 1 :
                   respons.sendRedirect("type_1_page");
              break;
              case 2 :
                   respons.sendRedirect("type_2_page");
              break;
              default :
                   repons.sendRedirect("/error500.jsp");
              break;
           }

        }else{

            this.getServletContext().getRequestDispatcher(your_jsp_relative_path).forward(request, respons);

        }
    }
}

Answer 2

在您的 loginControllerServlet.java 中将其更改为

if(theUser.getType()==p)

至此

if(theUser.getType().equals(p))

验证用户后根据用户角色重定向页面

Redirect the page according to the user role after validating user

java

jsp

servlets