時刻表示

     

●サンプル

bimport java.awt.Color;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.lang.String;
import java.util.Date;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

public class DigitalClock extends JFrame {
  final static int C00 = 1000;
  public DigitalClock() {
    DrawPanel L00 = new DrawPanel();  //デジタル時計の時刻を表示
    add(L00);
    new Timer(C00, L00).start();
  }

  public static void main(String[] A00) {
    Toolkit.getDefaultToolkit().setDynamicLayout(true);  //レイアウトの再評価

    DigitalClock L00 = new DigitalClock();
    L00.setTitle("デジタル時計");
    L00.setDefaultCloseOperation(EXIT_ON_CLOSE);
    L00.setBackground(Color.white);
    L00.setSize(200, 100);
    L00.setVisible(true);
  }
}

class DrawPanel extends JPanel implements ActionListener {

  public DrawPanel() {
    setBackground(Color.white);
  }

  public void actionPerformed(ActionEvent A00) {
    repaint();
  }

  public void paintComponent(Graphics A00) {
    super.paintComponent(A00);

    String L00 = String.format("%1$tp %1$tI:%1$tM:%1$tS", new Date());

    FontMetrics L01 = A00.getFontMetrics();

    A00.drawString(L00, (getWidth() - L01.stringWidth(L00)) / 2,
        (getHeight() + L01.getAscent() - L01.getDescent()) / 2);
  }
}



  

●実行結果