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Java in a Nutshell

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6.3 Drawing Graphics

Example 6.2 shows a fancier version of our simple applet. As you can see from Figure 6.2 , we've made the graphical display more interesting. This applet also does all of its drawing in the paint() method. It demonstrates the use of Font and Color objects.

This example also introduces the init() method, which is used, typically in place of a constructor, to perform any one-time initialization that is necessary when the applet is first created. The paint() method may be invoked many times in the life of an applet, so this example uses init() to create the Font object that paint() uses.

Figure 6.2: A fancier applet

[Graphic: Figure 6-2]

Example 6.2: An Applet with Fancier Graphics

import java.applet.*;
import java.awt.*;
public class SecondApplet extends Applet {
  static final String message = "Hello World";
  private Font font;
  // One-time initialization for the applet
  // Note: no constructor defined.
  public void init() {
    font = new Font("Helvetica", Font.BOLD, 48);
  // Draw the applet whenever necessary.  Do some fancy graphics.
  public void paint(Graphics g) {
    // The pink oval
    g.fillOval(10, 10, 330, 100);
    // The red outline. Java doesn't support wide lines, so we
    // try to simulate a 4-pixel wide line by drawing four ovals.
    g.drawOval(10, 10, 330, 100);
    g.drawOval(9, 9, 332, 102);
    g.drawOval(8, 8, 334, 104);
    g.drawOval(7, 7, 336, 106);
    // The text
    g.drawString(message, 40, 75);

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