loginValidation.jsp

<%--
    Document   : loginValidation
    Created on : Apr 28, 2017, 9:42:01 PM
    Author     : Sam
--%>

<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.Statement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%
    Connection connection = null;
    try {
        boolean checkLogin = false;
        String group = "";

        //get parameter from login.jsp
        String UserID = request.getParameter("UserID");
        String Password = request.getParameter("Password");

        //open database connection
        Class.forName("org.gjt.mm.mysql.Driver");
        String url = "jdbc:mysql://localhost/sterlingdeliverysystem";
        String user = "root";
        String pwd = "";
        connection = DriverManager.getConnection(url, user, pwd);
        Statement statement = connection.createStatement();

        String querySelect = "select * from sterling_login, sterling_customer where sterling_login.UserID = sterling_customer.UserID";

        ResultSet rows = statement.executeQuery(querySelect);

        while (rows.next()) {
            if ((rows.getString("sterling_login.UserID").equals(UserID)) && (rows.getString("sterling_login.Password").equals(Password))) {
                checkLogin = true;
                group = "Customer";
            }
        }

        String querySelect2 = "select * from sterling_login, sterling_employee where sterling_login.UserID = sterling_employee.UserID";

        ResultSet rows2 = statement.executeQuery(querySelect2);

        while (rows2.next()) {
            if ((rows2.getString("sterling_login.UserID").equals(UserID)) && (rows2.getString("sterling_login.Password").equals(Password)) && (rows2.getString("sterling_employee.Designation").equals("M"))) {
                checkLogin = true;
                group = "Manager";
            }
            else if ((rows2.getString("sterling_login.UserID").equals(UserID)) && (rows2.getString("sterling_login.Password").equals(Password)) && (rows2.getString("sterling_employee.Designation").equals("C"))) {
                checkLogin = true;
                group = "Clerk";
            }
            else if ((rows2.getString("sterling_login.UserID").equals(UserID)) && (rows2.getString("sterling_login.Password").equals(Password)) && (rows2.getString("sterling_employee.Designation").equals("D"))) {
                checkLogin = true;
                group = "DeliveryBoy";
            }
        }

        if (checkLogin == true) {
            session.setAttribute("UserID", UserID);
            session.setAttribute("Group", group);
            out.println("<script>alert('Login successful. Redirecting to Homepage.');document.location.href='index.jsp';</script>");
        }
        else
            out.println("<script>alert('Login credentials does not match. Please try again.');window.history.back();</script>");

    } catch (Exception e) {
        out.println("Error" + e);
        System.out.println("Error" + e);
        //It is a good practice to use System.out.println()
        //for printing the error messages in the server console
    } finally {
        if (null != connection) {
            connection.close();
        }
    }

%>