change to soap request

this is my form

<%@ 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="welcome" method="post">
<table align="left">
 <tr><td>Name<input type="text" name="name"></td></tr>
 <tr><td>Age<input type="text" name="age"></td></tr>
 <tr><td>City<input type="text" name="city"></td></tr>
 <tr><td>Course<input type="text" name="course"></td></tr>
<tr><td>username<input type="text" name="username"></td></tr>
<tr><td>password<input type="text" name="password"></td></tr>
<tr><td><input type="submit" name="action" value="New" width=50/></td></tr> 
</table>
</form>

<form action="welcome" method="post">
<table align="right">
<tr><td>username<input type="text" name="username"></td></tr>
<tr><td>password<input type="text" name="password"></td></tr>
<tr><td><input type="submit" name="action" value="Old" width=50/></td></tr> 
</table>
</form>

</body>
</html>

this is a servlet

package voter.servlet;

import java.io.IOException;
import java.io.PrintWriter;

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

public class WelcomeProcessor extends GenericProcessors {
	
       
   
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		this.doGet(request, response);
	}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		/*if(!isUserPresent(request)){
			response.sendRedirect("error.jsp");
		}
		*/
		PrintWriter out=response.getWriter();
		out.println("DOPOST");
		
		String action=request.getParameter("action");
		
		
		
		if(action.equals("New")){
			out.println("NEWWWWWWWW "+action);
			String name=request.getParameter("name");
			String age=request.getParameter("age");
			String city=request.getParameter("city");
			String course=request.getParameter("course");
			String username=request.getParameter("username");
			String password=request.getParameter("password");
			
			dbHandler.addStudent(name, age, city, course, username, password);
		}
		else if(action.equals("Old")){
			
			out.println("OLDDDDDDD "+action);
			
			String username=request.getParameter("username");
			String password=request.getParameter("password");
			
			boolean checkStudent=dbHandler.checklogin(username, password);
			if(checkStudent){
				addUser(username, request);
				out.println("User is authenticated");
				response.sendRedirect("welcome.jsp");
			}
			else{
				out.println("User is not authenticated");
			}
		}
	}

}

this is database class

package voter.db;

import java.sql.*;

public class DbHandler {
	
	Connection connection;

public DbHandler() {
		establishConnection();
	}

private void establishConnection(){
		try {
			
			Class.forName("com.mysql.jdbc.Driver");
			connection = DriverManager.getConnection(
					"jdbc:mysql://localhost:3306/form", "root","");
			
		} catch (ClassNotFoundException e) {			
			e.printStackTrace();
		} catch (SQLException e) {			
			e.printStackTrace();
		}
		
	}
	
	public void addStudent(String name,String age,String city,String course,String username,String password){
		
		PreparedStatement prepare=null;
		
		try {
			
			prepare=connection.prepareStatement("Insert Into " +
							"Student Values(?,?,?,?,?,?)");
			
			prepare.setString(1, name);
			prepare.setString(2, age);
			prepare.setString(3, city);
			prepare.setString(4, course);
			prepare.setString(5, username);
			prepare.setString(6, password);
			
			prepare.executeUpdate();
			prepare.close();
			
		} catch (SQLException e) {
			
			e.printStackTrace();
		}
		finally{
			try {
				prepare.close();
				connection.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			
			
		}
		
	}
	
	public boolean checklogin(String username,String password){
		
		boolean login=false;
		ResultSet re=null;
		PreparedStatement statement=null;
		
		try {
			//Statement statement=connection.createStatement();
			//ResultSet result=statement.executeQuery("SELECT * FROM student WHERE username=" + "'" + username + "'");
								
			statement=connection.prepareStatement("SELECT * FROM student WHERE username=? ");
			statement.setString(1,username);
			re=statement.executeQuery();
			
			
			while(re.next()){
				
				String pass=re.getString("password");
				System.out.println("valu of pass "+pass);
				if(pass.equals(password)){
					login=true;
					break;
				}
				
			}
			
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally{
			try {
				re.close();
				statement.close();
				connection.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		
		return login;
	}
}

currently it goes to server as HTTPS.
i need to change this as a send to Soap request to the server.
how should i change my code?

Hi!
I am assuming that you at least attempt to use some kind of MVC-like pattern:
The UI part does not need any changes.
The controller (servlet) needs to be injected with a web service client, to which it delegate the work. You should also remove all references to the database handler from the controller.
The database part does not need any changes, but instead of being injected into the controller, it should be injected into the web service class.
Additionally, you need to implement the web service.
Best wishes!