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Chapter 7 Generating the Server Response: HTTP Response Headers

Listing 7.9  MessageImage.java (continued)

public class MessageImage {

  /** Creates an Image of a string with an oblique

   *  shadow behind it. Used by the ShadowedText servlet

   *  and the ShadowedTextFrame desktop application.

   */

  public static Image makeMessageImage(String message,

                                       String fontName,

                                       int fontSize) {

    Frame f = new Frame();

    // Connect to native screen resource for image creation.

    f.addNotify();

    // Make sure Java knows about local font names.

    GraphicsEnvironment env = 

      GraphicsEnvironment.getLocalGraphicsEnvironment();

    env.getAvailableFontFamilyNames(); 

    Font font = new Font(fontName, Font.PLAIN, fontSize);

    FontMetrics metrics = f.getFontMetrics(font);

    int messageWidth = metrics.stringWidth(message);

    int baselineX = messageWidth/10;

    int width = messageWidth+2*(baselineX + fontSize);

    int height = fontSize*7/2;

    int baselineY = height*8/10;

    Image messageImage = f.createImage(width, height);

    Graphics2D g2d =

      (Graphics2D)messageImage.getGraphics();

    g2d.setFont(font);

    g2d.translate(baselineX, baselineY);

    g2d.setPaint(Color.lightGray);

    AffineTransform origTransform = g2d.getTransform();

    g2d.shear( 0.95, 0);

    g2d.scale(1, 3);

    g2d.drawString(message, 0, 0);

    g2d.setTransform(origTransform);

    g2d.setPaint(Color.black);

    g2d.drawString(message, 0, 0);

    return(messageImage);

  }

  /** Uses GifEncoder to send the Image down output stream

   *  in GIF89A format. See http://www.acme.com/java/ for

   *  the GifEncoder class.

   */

  public static void sendAsGIF(Image image, OutputStream out) {

    try {

      new GifEncoder(image, out).encode();

    } catch(IOException ioe) {

      System.err.println("Error outputting GIF: " + ioe);

    }

  }

}

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