how to dispose login page

import java.awt.*;
import javax.swing.*;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JPanel;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JComponent;
import javax.swing.JFrame;

public class login {
JLabel lbluserid, lblpass, image;
JTextField txtuserid;
JPasswordField tppass;
JButton blogin;
JFrame frame;
JPanel panel1;
ImageIcon icon;

public login(){

frame = new JFrame(".:: LOGIN ::.");
frame.setSize(300, 200);
frame.setResizable(false);
frame.setLayout(null);

JPanel panel1 = new JPanel(null);
panel1.setBorder(BorderFactory.createTitledBorder( "LOGIN"));
JLabel lbluserid = new JLabel("USER ID :");
JLabel lblpass = new JLabel ("PASSWORD :");
final JTextField txtuserid = new JTextField ();
final JPasswordField tppass = new JPasswordField();
JButton blogin = new JButton("LOGIN");
final JLabel image = new JLabel();
icon = new ImageIcon("IMRAN.jpg");

panel1.add(lbluserid);
panel1.add(lblpass);
panel1.add(txtuserid);
panel1.add(tppass);
panel1.add(blogin);
panel1.add(image);
frame.add(panel1);

panel1.setBounds(0,0,300,200);
image.setBounds(0,0,300,200);
lbluserid.setBounds(30,30,100,20);
lblpass.setBounds(30,60,100,20);
txtuserid.setBounds(140,30,100,20);
tppass.setBounds(140,60,100,20);
blogin.setBounds(80,120,80,20);

ImageIcon img = new ImageIcon("login.jpg")
{

@Override
public void paintIcon(Component c, Graphics g, int x, int y)
{
g.drawImage(getImage(), x, y, c.getWidth(), c.getHeight(), c);
}

@Override
public int getIconHeight()
{
return image.getHeight();
}

@Override
public int getIconWidth()
{

return image.getWidth();
}
};
image.setIcon(img);

blogin.addActionListener(new java.awt.event.ActionListener() {

public void actionPerformed(java.awt.event.ActionEvent evt) {
String id = txtuserid.getText();
char p[] = tppass.getPassword();
String psw = new String(p);
if( (id.equals( "admin")) && (psw.equals( "123"))){

JOptionPane.showMessageDialog(null,"Login Successful !!!");
gui obj1=new gui();
loading obj2=new loading();
obj2.liquid();
frame.dispose();
}else{

JOptionPane.showMessageDialog(null,"Wrong User Name/ password !!!");
}
}
});

frame.setFocusable(true);
frame.setVisible(true);
frame.setLocationRelativeTo(null);

}

}

here frame.dispose() didnot work and obj.loading() didnot work properly