ColorBox

import java.applet.Applet;
import java.awt.Button;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class RGB16 extends Applet implements ActionListener {
  private static final long serialVersionUID = 1L;
  private TextField fred, fgreen, fblue, fhex;
  private Button a, b;
  private Color color;

  @Override
  public void init() {
    color = Color.BLACK;
    fred = new TextField("0", 4);
    add(fred);
    fgreen = new TextField("0", 4);
    add(fgreen);
    fblue = new TextField("0", 4);
    add(fblue);
    a = new Button(">");
    a.addActionListener(this);
    add(a);
    b = new Button("<");
    b.addActionListener(this);
    add(b);
    fhex = new TextField("000000", 8);
    add(fhex);
  }

  @Override
  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == a) {
      int red = Integer.parseInt(fred.getText());
      int green = Integer.parseInt(fgreen.getText());
      int blue = Integer.parseInt(fblue.getText());
      color = new Color(red, green, blue);
      fred.setText("" + color.getRed());
      fgreen.setText("" + color.getGreen());
      fblue.setText("" + color.getBlue());
      fhex.setText("" +
        Integer.toString(((red << 16) | (green << 8) | blue), 16));
    }
    else if (e.getSource() == b) {
      int red = (Integer.parseInt(fhex.getText(), 16) & 0xff0000) >> 16;
      int green = (Integer.parseInt(fhex.getText(), 16) & 0xff00) >> 8;
      int blue = Integer.parseInt(fhex.getText(), 16) & 0xff;
      color = new Color(red, green, blue);
      fred.setText("" + color.getRed());
      fgreen.setText("" + color.getGreen());
      fblue.setText("" + color.getBlue());
      fhex.setText("" +
        Integer.toString(((red << 16) | (green << 8) | blue), 16));
    }
    repaint();
  }

  @Override
  public void paint(Graphics g) {
    g.setColor(color);
    g.fillRect(60, 60, 180, 60);
  }
}