import java.sql.*;
import javax.swing.*;

public class javaconnect {
public  static Connection ConnecDB(){
      Connection conn = null;
      String url = "jdbc:mysql://localhost:3306/testing";
      String driver = "com.mysql.jdbc.Driver";
      String user = "root";
      String pass = "root";
       try {
           Class.forName(driver);
           conn = DriverManager.getConnection(url, user, pass);
             if (conn == null) {
                      System.out.println("Connection cannot be established");
                 }
                       System.out.println("Connected to database");
                       return conn;
             } catch (Exception e) {
                     System.out.println(e);
            }
                       return null;

}

import java.awt.*;
import java.sql.*;
import javax.swing.*;


public class Login extends javax.swing.JFrame {
      Connection conn = null;
      ResultSet rs=null;
      PreparedStatement pst=null;

public Login() {
    initComponents();

}


private void txt_usernameActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:
}

private void cmd_loginActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:
    String sql = "select * from employee_info where username=? and password=?";
    try{
        pst=conn.prepareStatement(sql);
        pst.setString(1, txt_username.getText());
        pst.setString(2, txt_password.getText());

        rs=pst.executeQuery();
        if (rs.next()) {
            JOptionPane.showMessageDialog(null, "Login Sucessfully");
            employee_info  s = new employee_info();
            s.setVisible(true);
        }


        else{
             JOptionPane.showMessageDialog(null, "Incorrect Username or password");


        }
    }

    catch(Exception e){

        JOptionPane.showMessageDialog(null,e);

    }

}

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {


    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(Login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new Login().setVisible(true);
        }
    });
}