Program:-

Index.html:-

<!DOCTYPE html>

<html>

    <head>

        <title>Servlet</title>

        <meta charset="UTF-8">

        <meta name="viewport" content="width=device-width, initial-scale=1.0">

    </head>

    <body>

         <form method ="post" action="hello">

            Name <input type ="text" name="user">

            <input type="submit" value="submit">

        </form>

    </body>

</html>


Web.xml:- 

    <servlet>

        <servlet-name>HelloServlet</servlet-name>

        <servlet-class>HelloUser</servlet-class>

    </servlet>

    <servlet-mapping>

        <servlet-name>HelloServlet</servlet-name>

        <url-pattern>/hello</url-pattern>

    </servlet-mapping>

    <session-config>

        <session-timeout>

            30

        </session-timeout>

    </session-config>

</web-app>


HelloUser.java:-

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class HelloUser extends HttpServlet{
    protected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException{
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        String user = request.getParameter("user");
        out.println("<h2> Welcome \r\n"+user+"<h2>");
        
    }}

1st Interface of Web Application:-



After Inserting Name and Clicking submit Button:-