Looping Circle

Animations in Swing are typically achieved by repeatedly updating the position or properties of components and then redrawing them. The simplest way to create animations is by using the javax.swing.Timer class to schedule periodic updates.

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

public class Main extends JPanel {
    private int x = 0; // Initial X position of the ball
    private final int y = 100; // Fixed Y position
    private final int DIAMETER = 50; // Diameter of the ball

    public Main() {
        Timer timer = new Timer(10, e -> {
            x += 2; // Move the ball to the right
            if (x > getWidth()) { // Reset position when it moves off screen
                x = -DIAMETER;
            }
            repaint(); // Redraw the panel
        });
        timer.start(); // Start the animation timer
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g); // Clears the panel for fresh drawing
        g.setColor(Color.RED);  // Set ball color
        g.fillOval(x, y, DIAMETER, DIAMETER); // Draw the ball
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("Simple Animation");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 300);
        frame.add(new Main());
        frame.setVisible(true);
    }
}