import java.awt.*;
import java.awt.event.*;

public class Agency extends Frame implements ActionListener
{
Label l1,l2,l3,l4;
Button b1;
TextField t1,t2;
String s1,s2,s3,s4;


public static void main(String args[])
{
new Agency().setVisible(true);
}

public Agency()
{
super("Gas Agency Package");
setSize(1280,800);
setBackground(Color.lightGray);
setLayout(null);
// setLayout(new BorderLayout());


t1=new TextField(20);
t1.setBounds(440,150,200,30);
t1.setBackground(Color.white);
t2=new TextField(20);
t2.setBounds(440,180,200,30);
t2.setBackground(Color.white);
t2.setEchoChar('*');

l1=new Label("Gas Agency Package");
l1.setBounds(400,30,300,50);

l1.setFont(new Font("TimesRoman",Font.BOLD,25));
l1.setAlignment(Label.CENTER);

l2=new Label("Enter your ID and Passoword");
l2.setFont(new Font("TimesRoman",Font.BOLD,20));
l2.setBounds(270,80,300,50);

l3=new Label("Enter ID");
l2.setFont(new Font
("TimesRoman",Font.BOLD,20));
l3.setBounds(270,150,120,50);

l4=new Label("Enter Passoword");
l2.setFont(new Font
("TimesRoman",Font.BOLD,20));
l4.setBounds(270,180,140,50);

add(l1);
add(l2);
add(l3);
add(t1);
add(l4);
add(t2);


b1=new Button("Login");
b1.setBackground(Color.white);
b1.setBounds(400,280,100,70);
b1.addActionListener(this);
add(b1);

}

public void actionPerformed(ActionEvent e)
{

if(e.getSource()==b1)
{
s3="svce";
s4="svce";
s1=t1.getText();
s2=t2.getText();
if(s1.equals(s3) && s2.equals(s4))
{
//System.out.println("password is
correct");
MenuForm m= new MenuForm();
m.setVisible(true);
//this.dispose();
}
else
{
System.out.println("password not
correct");
}
this.dispose();

}
}
}

plzzzzzzz xplain me this java code like why i m including
this packages n the whole code plzzzzzz