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javajspservletspostservlet-listeners

JSP page not working in Servlet Program

Actually i'm trying to display the details obtained from JSP form with servlet. But I'm not able to display the JSP page. But I can see the program entering into the POST method in Servlet.

Here is my code,

Startup.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>Insert title here</title>
</head>
<body>
 <form action="controlServlets" method="post">
        <input type="text" name="name"/><br>        
        <input type="text" name="group"/>
        <input type="text" name="pass"/>
        <input type="submit" value="submit">            
    </form>

</body>
</html>

web.xml

<web-app>

  <servlet>
    <servlet-name>controlServlets</servlet-name>
    <servlet-class>com.selenium8x8.servlet.ControlServlets</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>controlServlets</servlet-name>
    <url-pattern>/*</url-pattern>
  </servlet-mapping>

</web-app>

ControlServlets.java

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/ControlServlets")
public class ControlServlets extends HttpServlet {
    private static final long serialVersionUID = 1L;


    public ControlServlets() {
        super();
        // TODO Auto-generated constructor stub
    }


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

        doPost(request,response);  
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

            String name = request.getParameter("name");
            String group = request.getParameter("group");
            String pass = request.getParameter("pass");
            System.out.println("Name :"+ name);
            System.out.println("group :"+ group);
            System.out.println("pass :"+ pass);
            System.out.println("Post method");
    }

}

In console,

I can see the following,

Name :null
group :null
pass :null
Post method

Please Help...

Solution

  • Part I)If you want to use web.xml for your application then you need to make following changes :

    1)In Startup.jsp change the action attribute of <form> tag to 

    <form action="ControlServlets" method="post"> 
              ↑

    2)In web.xml change the <servlet-mapping> to 

    <servlet-mapping>
 <servlet-name>controlServlets</servlet-name>
 <url-pattern>/ControlServlets</url-pattern> 
</servlet-mapping>

    3)In ControlServlets.java several changes as, in web.xml you mentioned 

    <servlet-class>com.selenium8x8.servlet.ControlServlets</servlet-class>
                ↑

    This is the package name, so you must have first statement in ControlServlets.java 

    package com.selenium8x8.servlet;  //in your code it is missing

    Then, comment following two lines 

    //import javax.servlet.annotation.WebServlet;

    and 

    //@WebServlet("/ControlServlets")

    Now, run application, it will give you desired output.

    Part II) If you want to use @WebServlet annotation, as you did

    import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/ControlServlets")
public class ControlServlets extends HttpServlet {   
  ...
  .....
  .......
}

    Then, no need for web.xml. The above does basically the same as following: 

    <servlet>
 <servlet-name>controlServlets</servlet-name>
 <servlet-class>com.selenium8x8.servlet.ControlServlets</servlet-class>
</servlet>
<servlet-mapping>
 <servlet-name>controlServlets</servlet-name>
 <url-pattern>/ControlServlets</url-pattern>
</servlet-mapping>

    For using @WebServlet annotation you need Java EE 6 / Servlet 3.0