FirstServlet.java

/*
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/**
 *
 * @author jacobjohn
 */
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;

class Login {
    public static boolean validate(String name, String pass) {
        boolean status = false;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con = DriverManager.getConnection(
                    "jdbc:mysql://localhost:3306/JavaJDBC?autoReconnect=true&useSSL=false", "root", "MyNewPass");

            PreparedStatement ps = con.prepareStatement("select * from userreg where name=? and pass=?");
            ps.setString(1, name);
            ps.setString(2, pass);

            ResultSet rs = ps.executeQuery();
            status = rs.next();

        } catch (Exception e) {
            System.out.println(e);
        }
        return status;
    }
}

public class FirstServlet extends HttpServlet {
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        response.setContentType("text/html");
        PrintWriter out = response.getWriter();

        String n = request.getParameter("username");
        String p = request.getParameter("userpass");

        if (Login.validate(n, p)) {
            RequestDispatcher rd = request.getRequestDispatcher("servlet2");
            rd.forward(request, response);
        } else {
            out.print("Sorry username or password error");
            RequestDispatcher rd = request.getRequestDispatcher("index.html");
            rd.include(request, response);
        }

        out.close();
    }
}