使用DAO将值从Java类传递到jsp页面

一尘不染

使用DAO将值从Java类传递到jsp页面

jsp

我想将在Java类上检索到的值传递给页面。我正在使用DAO类。我已经从数据库中检索出值并将它们存储在String变量中。现在我想将它们设置为view.jsp页面中的文本框。我是该领域的新手，有人可以帮助我吗？

View.jsp 是

<%@ 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>Insert title here</title>
    </head>
    <body>

    <form action="process.jsp">
    Enter Name    <br/> <br> <input type="text" name="uname"  onclick="this.value=''"/><br/><br/>

    <input type="submit" value="view details"/><br/><br/>
    Email id:   <br/> <input type="text"  name="email"  id="email" > <br/><br/>
    password:   <br/> <input type="text"  name="passw"  id="passw"><br/><br/>

    </form>        
    </body>
    </html>

和我的活动 ViewDAO.java 是

 public static void  view(user u) {
    Connection con=ConnectionProvider.getCon(); 
    String uname=u.getUname();
    try {
        PreparedStatement ps=con.prepareStatement("select email,pass from  S1.USER432 where name='"+uname+"'");
        ResultSet rs = ps.executeQuery();

        while (rs.next()) {

            String email = rs.getString("EMAIL");
            String pass = rs.getString("PASS");

            }

    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    }
}

谢谢…

阅读 313

2020-06-08

共1个答案

一尘不染

您需要像下面这样从servlet调用DAO方法：

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

      // call DAO method to get the email and password
    HashMap<String,String> map=ViewDAO.getDetails();

    //from the map you will get the  email and password.then you need to set them in the attributes and get them in your jsp

     request.setAttribute("email", map.get("email"));
      request.setAttribute("password", map.get("password"));

}

您的DAO方法应如下所示：

public static HashMap<String,String>  getDetails(user u) {
    Connection con=ConnectionProvider.getCon(); 
    String uname=u.getUname();
    Map<String,String> map=new HashMap<>();
    try {
        PreparedStatement ps=con.prepareStatement("select email,pass from  S1.USER432 where name='"+uname+"'");
        ResultSet rs = ps.executeQuery();

        while (rs.next()) {

            String email = rs.getString("EMAIL");
            String pass = rs.getString("PASS");

            }
       map.put("email",email);
       map.put("password",pass);


    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }       
    return map;
    }
}

希望这会帮助你。

2020-06-08