Assignment-1

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import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;

public class SimpleAwt extends Frame {
    public static void main(String args[])
 {
        JFrame frame = new JFrame();
        JButton button = new JButton("click");
        Container c = frame.getContentPane();
        c.setBackground(Color.WHITE);
        FlowLayout ff = new FlowLayout();
        c.setLayout(ff);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(button);
        button.addActionListener(new ActionListener() {
    
            public void actionPerformed(ActionEvent e) {
                changeColor(c);
            }
        });
        frame.setSize(300, 300);
        frame.setVisible(true);
    }
    public static void changeColor(Container c) {
        Color cc = c.getBackground();
        if (cc.equals(Color.WHITE)) {
            c.setBackground(Color.RED);
        } else if (cc.equals(Color.RED)) {
            c.setBackground(Color.GREEN);
        } else if (cc.equals(Color.GREEN)) {
            c.setBackground(Color.BLUE);
        } else if (cc.equals(Color.BLUE)) {
            c.setBackground(Color.WHITE);
        }
    }

} 

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