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Chapter 16 - Multimedia: Images, Animation, Audio and Video

Chapter 16 - Multimedia: Images, Animation, Audio and Video. Outline 16.1 Introduction 16.2 Downloading the Java Media Framework 16.3 Loading, Displaying and Scaling Images 16.4 Loading and Playing Audio Clips 16.5 The Java Media Player 16.6 Animating a Series of Images

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Chapter 16 - Multimedia: Images, Animation, Audio and Video

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  1. Chapter 16 - Multimedia: Images, Animation, Audio and Video Outline 16.1 Introduction 16.2 Downloading the Java Media Framework 16.3 Loading, Displaying and Scaling Images 16.4 Loading and Playing Audio Clips 16.5 The Java Media Player 16.6 Animating a Series of Images 16.7 Animation Issues 16.8 Customizing Applets via the HTML param Tag 16.9 Image Maps 16.10 Java Plug-In 16.11 Internet and World Wide Web Resources

  2. 16.1 Introduction • Revolution in computer industry • Before, computers used for high-speed calculations • Now, data manipulation important • Multimedia • "Sizzle" of Java - images, sound, video • CDs, DVDs, video cards • Demands extraordinary computing power • Fast processors making multimedia possible • Java • Built-in multimedia capabilities • Most programming languages do not • Develop powerful multimedia applications

  3. 16.2 Downloading the Java Media Framework • Java media framework (JMF) • Extension to Java API • Enhanced processing of images, audio, and video • Constantly evolving • Some examples required the JMF, not included in J2SDK http://java.sun.com/products/java-media/jmf/1.1/ • JMF Downloads for Windows and Solaris • At time of writing, early versions of JMF 2.0 available http://java.sun.com/products/java-media/jmf/index.html

  4. 10 private Image logo1; 16 logo1 = getImage( getDocumentBase(), "logo.gif" ); 16.2 Loading, Displaying and Scaling Images • Java Multimedia • Discuss graphics, images, animations, sounds, and video • Begin with images • Class Image (java.awt) • Abstract class, cannot create an object directly • Request Image be loaded and returned • getImage( imageLocation, filename ); • Of class Applet (superclass of JApplet) • imageLocation • getDocumentBase() is URL (address) of HTML file • filename - .gif or .jpg (.jpeg)

  5. 24 g.drawImage( logo1, 0, 0, this ); 16.2 Loading, Displaying and Scaling Images • Displaying Images • Method drawImage (class Graphics) • Many overloaded versions g.drawImage( myImage, x, y, ImageObserver ); • myImage - Image object • x,y - coordinates to display image • ImageObserver - object on which image is displayed • Use "this" to indicate the applet • Can be any object that implements ImageObserver interface

  6. 28 g.drawImage( logo1, 0, 120, 29 getWidth(), getHeight() - 120, this ); 16.2 Loading, Displaying and Scaling Images • Displaying Images • g.drawImage( myImage, x, y, width, height, ImageObserver ); • width and height • Dimensions of image (automatically scaled) • getWidth(), getHeight() • Returns dimensions of applet

  7. 11 private ImageIcon logo2; 17 logo2 = new ImageIcon( "logo.gif" ); 16.2 Loading, Displaying and Scaling Images • Class ImageIcon • Concrete class (can create objects) • Example constructor and initialization • Displaying Icons • Method paintIcon (class Graphics) myIcon.paintIcon( Component, Graphics, x, y ) • Component - Component object on which to display image (this) • Graphics - Graphics object used to render image (g) • x, y - coordinates of Icon

  8. 16.2 Loading, Displaying and Scaling Images • Usage • ImageIcons simpler than Images • Create objects directly • No need for ImageObserver reference • All components are ImageObservers • Cannot scale ImageIcons • Scaling • Use ImageIcon method getImage • Returns Image reference • This can be used with drawImage and scaled

  9. 1// Fig. 16.1: LoadImageAndScale.java 2// Load an image and display it in its original size 3// and scale it to twice its original width and height. 4// Load and display the same image as an ImageIcon. Notice the parameters to the constructors. Image objects cannot be created directly. 5import java.applet.Applet; 6import java.awt.*; 7import javax.swing.*; 8 drawImage calls (second call has scaling). this means the image will be shown on the applet. 9public class LoadImageAndScale extends JApplet { 10 private Image logo1; 11 private ImageIcon logo2; 12 13 // load the image when the applet is loaded 14 public void init() 15 { 16 logo1 = getImage( getDocumentBase(), "logo.gif" ); 17 logo2 = new ImageIcon( "logo.gif" ); 18 } 19 20 // display the image 21 public void paint( Graphics g ) 22 { 23 // draw the original image 24 g.drawImage( logo1, 0, 0, this ); 25 26 // draw the image scaled to fit the width of the applet 27 // and the height of the applet minus 120 pixels 28 g.drawImage( logo1, 0, 120, 29 getWidth(), getHeight() - 120, this ); 1. Declare objects 2. init() 2.1 Initialize objects 3. paint() 3.1 drawImage

  10. 32 logo2.paintIcon( this, g, 180, 0 ); 33 } 34 } Call to paintIcon, displays icon on this applet (a Component). 30 31 // draw the icon using its paintIcon method 3.2 paintIcon Program Output

  11. 16.4 Loading and Playing Audio Clips • Audio clips • Require speakers and sound board • Sound engine - plays audio clips • Supports .au, .wav, .aif, .mid • Java Media Framework supports additional formats

  12. 16.4 Loading and Playing Audio Clips • Playing audio clips • play method in Applet • Plays clip once, marked for garbage collection when finished play( location, soundFileName ); location - getDocumentBase (URL of HTML file) play( soundURL ); soundURL - URL that contains location and filename of clip

  13. 46 sound1 = getAudioClip( 47 getDocumentBase(), "welcome.wav" ); 16.4 Loading and Playing Audio Clips • Playing audio clips • Method play from AudioClip interface • More flexible than Applet method play • Audio stored in program, can be reused • getAudioClip • Returns reference to an AudioClip • Same format as Applet method play • getAudioClip( location, filename ) • getAudioClip( soundURL )

  14. 66 currentSound.loop(); 68 currentSound.stop(); 64 currentSound.play(); 16.4 Loading and Playing Audio Clips • Playing audio clips • Once AudioClip loaded, use methods • play - plays audio once • loop - continuously loops audio in background • stop - terminates clip that is currently playing • Upcoming program • Use a JComboBox to select between two sounds

  15. 1// Fig. 16.2: LoadAudioAndPlay.java 2// Load an audio clip and play it. 3import java.applet.*; 4import java.awt.*; 5import java.awt.event.*; 6import javax.swing.*; 7 8public class LoadAudioAndPlay extends JApplet { 9 private AudioClip sound1, sound2, currentSound; Once the selection changes, stop currentSound and set it equal to either sound1 or sound2. 10 private JButton playSound, loopSound, stopSound; 11 private JComboBox chooseSound; 12 13 // load the image when the applet begins executing 14 public void init() 15 { 16 Container c = getContentPane(); 17 c.setLayout( new FlowLayout() ); 18 19 String choices[] = { "Welcome", "Hi" }; 20 chooseSound = new JComboBox( choices ); 21 chooseSound.addItemListener( 22 new ItemListener() { 23 public void itemStateChanged( ItemEvent e ) 24 { 25 currentSound.stop(); 26 27 currentSound = 28 chooseSound.getSelectedIndex() == 0 ? 29 sound1 : sound2; 1. Declare objects 1.1 GUI 1.2 Event handler 1.2.1 stop

  16. 33 c.add( chooseSound ); 34 35 ButtonHandler handler = new ButtonHandler(); 36 playSound = new JButton( "Play" ); 37 playSound.addActionListener( handler ); 38 c.add( playSound ); Notice how AudioClips are initialized. 39 loopSound = new JButton( "Loop" ); 40 loopSound.addActionListener( handler ); 41 c.add( loopSound ); Applet's stop method called when user switches web pages. Ensures clip stop playing (else could be annoying to user). 42 stopSound = new JButton( "Stop" ); 43 stopSound.addActionListener( handler ); 44 c.add( stopSound ); 45 46 sound1 = getAudioClip( 47 getDocumentBase(), "welcome.wav" ); 48 sound2 = getAudioClip( 49 getDocumentBase(), "hi.au" ); 50 currentSound = sound1; 51 } 52 53 // stop the sound when the user switches Web pages 54 // (i.e., be polite to the user) 55 public void stop() 56 { 57 currentSound.stop(); 58 } 59 30 } 31 } 32 ); 1.3 Register event handlers 2. Initialize AudioClips 3. Method stop

  17. 65 else if ( e.getSource() == loopSound ) 66 currentSound.loop(); 67 else if ( e.getSource() == stopSound ) 68 currentSound.stop(); Call methods play, loop, and stop as appropriate. 69 } 70 } 71 } 60 private class ButtonHandler implements ActionListener { 61 public void actionPerformed( ActionEvent e ) 62 { 63 if ( e.getSource() == playSound ) 64 currentSound.play(); 4. Event handler 4.1 play, loop, stop

  18. Play/pause Mute Volume Position indicator Information 16.5 The Java Media Player • Java Media Player • Comes with JMF • Can play • Audio: .au, .wav, .aiff, .mid • Video: .avi, .gsm, .mpg (.mpeg), .mov, .rmf, .rtp, .viv

  19. 16.5 The Java Media Player • JFileChooser (javax.swing) • Allows you to select a file

  20. 42 if ( result == JFileChooser.CANCEL_OPTION ) 43 file = null; 35 JFileChooser fileChooser = new JFileChooser(); 37 fileChooser.setFileSelectionMode( 38 JFileChooser.FILES_ONLY ); 39 int result = fileChooser.showOpenDialog( this ); 16.5 The Java Media Player • JFileChooser (javax.swing) • Create JFileChooser • Open only files (not directories) • Returns an integer indicating user's action (selected file or cancel) • If cancel, set file to null

  21. 44 else 45 file = fileChooser.getSelectedFile(); 10 private Player player; 57 player = Manager.createPlayer( file.toURL() ); 16.5 The Java Media Player • Otherwise, call getSelectedFile and assign result to file • Class File discussed next chapter • Returns object that implements Player interface (javax.media) • If file of correct format, returns object • Method toURL converts file name and location into URL format

  22. 58 player.addControllerListener( new EventHandler() ); 108 Component visualComponent = 59 player.start(); // start player 109 player.getVisualComponent(); 111 if ( visualComponent != null ) 112 c.add( visualComponent, BorderLayout.CENTER ); 16.5 The Java Media Player • Registers event handler • Interface ControllerListener, must define controllerUpdate • Takes ControllerEvent objects • Many subclasses, we use RealizeCompleteEvent subclass • Adds visual aspect of media clips • Audio clips return null

  23. 120 c.doLayout(); 73 player.close(); 114 Component controlsComponent = 115 player.getControlPanelComponent(); 117 if ( controlsComponent != null ) 118 c.add( controlsComponent, BorderLayout.SOUTH ); 16.5 The Java Media Player • Display controls • Update content pane • Programmer-defined method removePreviousPlayer • Close current player

  24. 75 Component visual = player.getVisualComponent(); 76 Component control = player.getControlPanelComponent(); 80 if ( visual != null ) 81 c.remove( visual ); 83 if ( control != null ) 84 c.remove( control ); 16.5 The Java Media Player • Get references to visual and control components • Container method remove • Remove Components from interface

  25. 1 // Fig. 16.3: MediaPlayerDemo.java 2 // Uses a Java Media Player to play media files. 3 import java.awt.*; 4 import java.awt.event.*; 5 import java.io.*; 6 import javax.swing.*; 7 import javax.media.*; 8 9 public class MediaPlayerDemo extends JFrame { 10 private Player player; 11 private File file; 12 13 public MediaPlayerDemo() 14 { 15 super( "Demonstrating the Java Media Player" ); 16 17 JButton openFile = new JButton( "Open file to play" ); 18 openFile.addActionListener( 19 new ActionListener() { 20 public void actionPerformed( ActionEvent e ) 21 { 22 openFile(); 23 createPlayer(); 24 } 25 } 26 ); 27 getContentPane().add( openFile, BorderLayout.NORTH ); 28 29 setSize( 300, 300 ); 30 show(); 31 } 1. Declarations 1.1 Constructor

  26. 32 41 // user clicked Cancel button on dialog 33 private void openFile() 42 if ( result == JFileChooser.CANCEL_OPTION ) Create a JFileChooser, use it to select a file. 34 { 43 file = null; 44 else 35 JFileChooser fileChooser = new JFileChooser(); Test for cancel option. If not, assign file to file. 36 45 file = fileChooser.getSelectedFile(); 37 fileChooser.setFileSelectionMode( 46 } 38 JFileChooser.FILES_ONLY ); 47 48 private void createPlayer() 39 int result = fileChooser.showOpenDialog( this ); Assign player result of createPlayer. Add event handler (named inner class), call start method to being playing clip. 40 49 { 50 if ( file == null ) 51 return; 52 53 removePreviousPlayer(); 54 55 try { 56 // create a new player and add listener 57 player = Manager.createPlayer( file.toURL() ); 58 player.addControllerListener( new EventHandler() ); 59 player.start(); // start player 60 } 2. Method openFile 2.1 JFileChooser 2.2 file 3. Method createPlayer 3.1 removePrevious Player 3.2 createPlayer 3.3 Event handler 3.4 start

  27. 61 catch ( Exception e ){ 62 JOptionPane.showMessageDialog( this, 63 "Invalid file or location", "Error loading file", 64 JOptionPane.ERROR_MESSAGE ); Get references to Components and remove them from content pane. Close the current player 65 } 66 } 67 68 private void removePreviousPlayer() 69 { 70 if ( player == null ) 71 return; 72 73 player.close(); 74 75 Component visual = player.getVisualComponent(); 76 Component control = player.getControlPanelComponent(); 77 78 Container c = getContentPane(); 79 80 if ( visual != null ) 81 c.remove( visual ); 82 83 if ( control != null ) 84 c.remove( control ); 85 } 86 87 public static void main(String args[]) 88 { 89 MediaPlayerDemo app = new MediaPlayerDemo(); 90 4. removePrevious Player 4.1 close 4.2 remove 5. main

  28. 91 app.addWindowListener( 92 new WindowAdapter() { 93 public void windowClosing( WindowEvent e ) 94 { 95 System.exit(0); 96 } Get Components and attach to content pane. 97 } 98 ); 99 } 100 101 // inner class to handler events from media player 102 private class EventHandler implements ControllerListener { 103 public void controllerUpdate( ControllerEvent e ) { 104 if ( e instanceof RealizeCompleteEvent ) { 105 Container c = getContentPane(); 106 107 // load Visual and Control components if they exist 108 Component visualComponent = 109 player.getVisualComponent(); 110 111 if ( visualComponent != null ) 112 c.add( visualComponent, BorderLayout.CENTER ); 113 114 Component controlsComponent = 115 player.getControlPanelComponent(); 116 117 if ( controlsComponent != null ) 118 c.add( controlsComponent, BorderLayout.SOUTH ); 6. Event handler 6.1 getVisualComponent 6.2 getControlPanel Component

  29. 119 120 c.doLayout(); 121 } 122 } 123 } 124 } 6.3 doLayout Program Output

  30. Program Output

  31. 16.6 Animating a Series of Images • Class Timer • Generates ActionEvents at a fixed interval in milliseconds • Constructor: Timer ( animationDelay, actionListener ); actionListener - ActionListener that will respond to ActionEvents • Methods • start • stop • restart • isRunning

  32. 30 super.paintComponent( g ); 16.6 Animating a Series of Images • Method repaint • Calls update, which calls paintComponent • Subclasses of JComponent should use paintComponent • Call superclass paintComponent first to display components properly

  33. 16.6 Animating a Series of Images • View area • Width and height specify entire window, not just client area • Client area - where components can be displayed • Dimension objects • Constructor • Dimension( width, height ) • Contains width and height instance variables • Method setSize( width, height ) • Class JFrame • Sets size of window

  34. 32 if ( images[ currentImage ].getImageLoadStatus() == 33 MediaTracker.COMPLETE ) { 16.6 Animating a Series of Images • getImageLoadStatus • ImageIconmethod • Determines if image is completely loaded into memory • Only complete images should be displayed (smooth animation) • If loaded, returns MediaTracker.COMPLETE • MediaTracker • Can determine when images are loaded, or force program to wait • ImageIcon creates our MediaTracker for us

  35. 16.6 Animating a Series of Images • Following example • Use a series of images stored in an array • Use Timer to generate ActionEvents • Change image displayed • Update content pane

  36. 1// Fig. 16.3: LogoAnimator.java 2// Animation a series of images 3import java.awt.*; 4import java.awt.event.*; 5import javax.swing.*; 6 Load array of ImageIcons to use for the animation. 7public class LogoAnimator extends JPanel 8 implements ActionListener { Call to superclass paintComponent ensures proper display. 9 protected ImageIcon images[]; 10 protected int totalImages = 30, 11 currentImage = 0, 12 animationDelay = 50; // 50 millisecond delay 13 protected Timer animationTimer; 14 15 public LogoAnimator() 16 { 17 setSize( getPreferredSize() ); 18 19 images = new ImageIcon[ totalImages ]; 20 21 for ( int i = 0; i < images.length; ++i ) 22 images[ i ] = 23 new ImageIcon( "images/deitel" + i + ".gif" ); 24 25 startAnimation(); 26 } 27 28 public void paintComponent( Graphics g ) 29 { 30 super.paintComponent( g ); 31 1.1 Class LogoAnimator ( implements ActionListener) 1.2 Declare objects 1.3 Constructor 1.4 Initialize ImageIcon array 2. paintComponent 2.1 super.paint Component

  37. 32 if ( images[ currentImage ].getImageLoadStatus() == 33 MediaTracker.COMPLETE ) { 34 images[ currentImage ].paintIcon( this, g, 0, 0 ); Check if the image has loaded, and if so, increment currentImage. 35 currentImage = ( currentImage + 1 ) % totalImages; 36 } Create new Timer, start. this applet listed as event handler. 37 } 38 39 public void actionPerformed( ActionEvent e ) 40 { If animationTimer is not running (i.e. user switched web pages and returned), restart it. 41 repaint(); 42 } 43 44 public void startAnimation() 45 { 46 if ( animationTimer == null ) { 47 currentImage = 0; 48 animationTimer = new Timer( animationDelay, this ); 49 animationTimer.start(); 50 } 51 else // continue from last image displayed 52 if ( ! animationTimer.isRunning() ) 53 animationTimer.restart(); 54 } 55 56 public void stopAnimation() 57 { 58 animationTimer.stop(); 59 } 60 2.2 getImage LoadStatus 2.3 Increment currentImage 3. actionPerformed 3.1 startAnimation 3.2 stopAnimation

  38. 65 66 public Dimension getPreferredSize() 67 { 68 return new Dimension( 160, 80 ); 69 } 70 71 public static void main( String args[] ) 72 { 73 LogoAnimator anim = new LogoAnimator(); 74 75 JFrame app = new JFrame( "Animator test" ); 76 app.getContentPane().add( anim, fBorderLayout.CENTER ); 77 78 app.addWindowListener( 79 new WindowAdapter() { 80 public void windowClosing( WindowEvent e ) 81 { 82 System.exit( 0 ); 83 } 84 } 85 ); 86 61 public Dimension getMinimumSize() 62 { 63 return getPreferredSize(); 64 } 3.3 getMinimumSize 3.4. getPreferredSize 4. main

  39. 87 // The constants 10 and 30 are used below to size the 88 // window 10 pixels wider than the animation and 89 // 30 pixels taller than the animation. 90 app.setSize( anim.getPreferredSize().width + 10, 91 anim.getPreferredSize().height + 30 ); 92 app.show(); 93 } 94} Program Output

  40. 16.7 Animation Issues • Storing images • Interlaced/non-interlaced formats • Specifies order in which pixels are stored • Non-interlaced - pixels stored in order they appear on screen • Image appears in chunks from top to bottom as it is loaded • Interlaced - pixels stored in rows, but out of order • Image appears to fade in and become more clear

  41. 16.7 Animation Issues • Animation flickers • Due to update being called in response to repaint • In AWT GUI components • Draws filled rectangle in background color where image was • Draw image, sleep, clear background (flicker), draw next image... • Swing's JPanel overrides update to avoid this

  42. 16.7 Animation Issues • Double buffering • Used to smooth animations • Program renders one image on screen • Builds next image in off-screen buffer • When time to display next image, done smoothly • Partial images user would have seen (while image loads) are hidden • All pixels for next image displayed at once • Space/Time tradeoff • Reduces flicker, but can slow animation speed and uses more memory • Used by Swing GUI components by default

  43. 16.8 Customizing Applets via the HTML param Tag • Applets • Customize through parameters in HTML file that invokes it <html><applet code="LogoApplet.class" width=400 height=400><param name="totalimages" value="30"><param name="imagename" value="deitel"><param name="animationdelay" value="200"></applet></html> • Invokes applet LogoApplet • param tags • Each has a name and a value • Use Applet method getParameter (returns a String) parameter = getParameter( "animationdelay" );

  44. 16.8 Customizing Applets via the HTML param Tag • Following example • Use the LogoAnimator class as before, but modified slightly • Include constructor to specify delay, name, number of images • Create Applet LogoApplet • Takes parameters • totalimages • imagename • animationdelay • Create LogoAnimator object using parameters(use new constructor) • Play animation

  45. 127 import java.awt.*; 128 import javax.swing.*; 129 The LogoAnimator class now has a new constructor. 130 public class LogoApplet extends JApplet{ 131 public void init() 132 { 7 public class LogoAnimator extends JPanel 133 String parameter; Get parameters from HTML file, convert to integers. 8 implements ActionListener { 134 135 parameter = getParameter( "animationdelay" ); Create new LogoAnimator, use custom constructor if applicable. 136 int animationDelay = ( parameter == null ? 50 : 137 Integer.parseInt( parameter ) ); 138 139 String imageName = getParameter( "imagename" ); 140 141 parameter = getParameter( "totalimages" ); 142 int totalImages = ( parameter == null ? 0 : 143 Integer.parseInt( parameter ) ); 144 145 // Create an instance of LogoAnimator 146 LogoAnimator animator; 147 148 if ( imageName == null || totalImages == 0 ) 22public LogoAnimator( int num, int delay, String name ) 149 animator = new LogoAnimator(); 150 else 151 animator = new LogoAnimator( totalImages, 152 animationDelay, imageName ); 1. LogoAnimator class as before, but with new constructor --------------------- 1.1 getParameter 1.2 LogoAnimator

  46. 153 154 setSize( animator.getPreferredSize().width, 155 animator.getPreferredSize().height ); 156 getContentPane().add( animator, BorderLayout.CENTER ); Start the animation. 157 158 animator.startAnimation(); 159 } 160 } 2. setSize 2.3 startAnimation Program Output

  47. 16.9 Image Maps • Image map • Image that has hot areas • User can click to accomplish a task • Bubble help • When mouse over particular point in screen, small message displayed in status bar • In the following example • Load image containing several icons • Use event handler mouseMoved to find x-coordinate • Based on the x-coordinate, display a message

  48. 1 // Fig. 16.7: ImageMap.java 2 // Demonstrating an image map. 3 import java.awt.*; 4 import java.awt.event.*; 5 import javax.swing.*; 6 7 public class ImageMap extends JApplet { Pass the x coordinate to translateLocation. This returns a String, which is passed to showStatus. 8 private ImageIcon mapImage; 9 private int width, height; 10 11 public void init() 12 { 13 addMouseListener( 14 new MouseAdapter() { 15 public void mouseExited( MouseEvent e ) 16 { 17 showStatus( "Pointer outside applet" ); 18 } 19 } 20 ); 21 22 addMouseMotionListener( 23 new MouseMotionAdapter() { 24 public void mouseMoved( MouseEvent e ) 25 { 26 showStatus( translateLocation( e.getX() ) ); 27 } 28 } 29 ); 30 1. Declare objects 2. init 2.1 addMouseListener

  49. 31 mapImage = new ImageIcon( "icons2.gif" ); 42 public String translateLocation( int x ) 32 width = mapImage.getIconWidth(); 43 { Determine width of mapimage. 33 height = mapImage.getIconHeight(); 44 // determine width of each icon (there are 6) 45 int iconWidth = width / 6; 34 setSize( width, height ); 35 } 46 36 47 if ( x >= 0 && x <= iconWidth ) Determine width of each icon in image. Based on this, display a message. 48 return "Common Programming Error"; 37 public void paint( Graphics g ) 38 { 49 else if ( x > iconWidth && x <= iconWidth * 2 ) 39 mapImage.paintIcon( this, g, 0, 0 ); 50 return "Good Programming Practice"; 40 } 51 else if ( x > iconWidth * 2 && x <= iconWidth * 3 ) 52 return "Performance Tip"; 41 53 else if ( x > iconWidth * 3 && x <= iconWidth * 4 ) 54 return "Portability Tip"; 55 else if ( x > iconWidth * 4 && x <= iconWidth * 5 ) 56 return "Software Engineering Observation"; 57 else if ( x > iconWidth * 5 && x <= iconWidth * 6 ) 58 return "Testing and Debugging Tip"; 2.2 Initialize ImageIcon 3. paint 4. translateLocation

  50. 59 60 return ""; 61 } 62 } Program Output

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