設定背景 自動變顏色，然後字型也變顏色

package day1127.test;

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

public class Test {

	public static void main(String[] args) {
		int width = 500, height = 300;
		JFrame jFrame = new JFrame();
		jFrame.setLayout(new BorderLayout());
		Font font = new Font("黑體", 0, 25);
		JLabel label = new JLabel("時間過的真快！");
		label.setFont(font);
		label.setForeground(Color.white);
		Panel panel = new Panel(new FlowLayout());
		panel.add(label);
		panel.setSize(width, height);
		panel.setBackground(Color.black);
		jFrame.add(panel);
		jFrame.setUndecorated(true);
		jFrame.setTitle("視窗變色");
		jFrame.setLocation((Toolkit.getDefaultToolkit().getScreenSize().width - width) / 2,
				(Toolkit.getDefaultToolkit().getScreenSize().height - height) / 2);
		jFrame.setSize(width, height);
		jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		jFrame.setVisible(true);

		new Thread(() -> {
			try {
				int i = 0;
				int j = 3;
				Color[] c = new Color[] { Color.black, Color.yellow, Color.blue, Color.cyan, Color.gray, Color.green,
						Color.lightGray, Color.magenta, Color.PINK, Color.red, Color.white, Color.yellow };
				while (true) {
					label.setForeground(c[i++]);
					i = i>=c.length ? 0:i;
					panel.setBackground(c[j++]);
					j = j>=c.length ? 0:j;
					Thread.sleep(500);
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		}).start();
	}
}