website login and registartion source code jsp java

package demotest; import java.io.IOException; import javax.servlet.RequestDispatcher;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class guru_register */public class guru_register extends HttpServlet {	private static final long serialVersionUID = 1L;                protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		// TODO Auto-generated method stub		String first_name = request.getParameter("first_name");		String last_name = request.getParameter("last_name");		String username = request.getParameter("username");		String password = request.getParameter("password");		String address = request.getParameter("address");		String contact = request.getParameter("contact");				if(first_name.isEmpty() || last_name.isEmpty() || username.isEmpty() || 				password.isEmpty() || address.isEmpty() || contact.isEmpty())		{			RequestDispatcher req = request.getRequestDispatcher("register_1.jsp");			req.include(request, response);		}		else		{			RequestDispatcher req = request.getRequestDispatcher("register_2.jsp");			req.forward(request, response);		}	} }