/* * @(#)ImageIcon.java 1.53 03/12/19 * * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package javax.swing; import java.awt.*; import java.awt.image.*; import java.net.URL; import java.io.Serializable; import java.io.ObjectOutputStream; import java.io.ObjectInputStream; import java.io.IOException; import java.util.Locale; import javax.accessibility.*; /** * An implementation of the Icon interface that paints Icons * from Images. Images that are created from a URL, filename or byte array * are preloaded using MediaTracker to monitor the loaded state * of the image. * *
* For further information and examples of using image icons, see * How to Use Icons * in The Java Tutorial. * *
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*
* @version 1.53 12/19/03
* @author Jeff Dinkins
* @author Lynn Monsanto
*/
public class ImageIcon implements Icon, Serializable, Accessible {
/* Keep references to the filename and location so that
* alternate persistence schemes have the option to archive
* images symbolically rather than including the image data
* in the archive.
*/
transient private String filename;
transient private URL location;
transient Image image;
transient int loadStatus = 0;
ImageObserver imageObserver;
String description = null;
protected final static Component component = new Component() {};
protected final static MediaTracker tracker = new MediaTracker(component);
/**
* Id used in loading images from MediaTracker.
*/
private static int mediaTrackerID;
int width = -1;
int height = -1;
/**
* Creates an ImageIcon from the specified file. The image will
* be preloaded by using MediaTracker to monitor the loading state
* of the image.
* @param filename the name of the file containing the image
* @param description a brief textual description of the image
* @see #ImageIcon(String)
*/
public ImageIcon(String filename, String description) {
image = Toolkit.getDefaultToolkit().getImage(filename);
if (image == null) {
return;
}
this.filename = filename;
this.description = description;
loadImage(image);
}
/**
* Creates an ImageIcon from the specified file. The image will
* be preloaded by using MediaTracker to monitor the loading state
* of the image. The specified String can be a file name or a
* file path. When specifying a path, use the Internet-standard
* forward-slash ("/") as a separator.
* (The string is converted to an URL, so the forward-slash works
* on all systems.)
* For example, specify:
*
* new ImageIcon("images/myImage.gif")* The description is initialized to the
filename
string.
*
* @param filename a String specifying a filename or path
* @see #getDescription
*/
public ImageIcon (String filename) {
this(filename, filename);
}
/**
* Creates an ImageIcon from the specified URL. The image will
* be preloaded by using MediaTracker to monitor the loaded state
* of the image.
* @param location the URL for the image
* @param description a brief textual description of the image
* @see #ImageIcon(String)
*/
public ImageIcon(URL location, String description) {
image = Toolkit.getDefaultToolkit().getImage(location);
if (image == null) {
return;
}
this.location = location;
this.description = description;
loadImage(image);
}
/**
* Creates an ImageIcon from the specified URL. The image will
* be preloaded by using MediaTracker to monitor the loaded state
* of the image.
* The icon's description is initialized to be
* a string representation of the URL.
* @param location the URL for the image
* @see #getDescription
*/
public ImageIcon (URL location) {
this(location, location.toExternalForm());
}
/**
* Creates an ImageIcon from the image.
* @param image the image
* @param description a brief textual description of the image
*/
public ImageIcon(Image image, String description) {
this(image);
this.description = description;
}
/**
* Creates an ImageIcon from an image object.
* If the image has a "comment" property that is a string,
* then the string is used as the description of this icon.
* @param image the image
* @see #getDescription
* @see java.awt.Image#getProperty
*/
public ImageIcon (Image image) {
this.image = image;
Object o = image.getProperty("comment", imageObserver);
if (o instanceof String) {
description = (String) o;
}
loadImage(image);
}
/**
* Creates an ImageIcon from an array of bytes which were
* read from an image file containing a supported image format,
* such as GIF, JPEG, or (as of 1.3) PNG.
* Normally this array is created
* by reading an image using Class.getResourceAsStream(), but
* the byte array may also be statically stored in a class.
*
* @param imageData an array of pixels in an image format supported
* by the AWT Toolkit, such as GIF, JPEG, or (as of 1.3) PNG
* @param description a brief textual description of the image
* @see java.awt.Toolkit#createImage
*/
public ImageIcon (byte[] imageData, String description) {
this.image = Toolkit.getDefaultToolkit().createImage(imageData);
if (image == null) {
return;
}
this.description = description;
loadImage(image);
}
/**
* Creates an ImageIcon from an array of bytes which were
* read from an image file containing a supported image format,
* such as GIF, JPEG, or (as of 1.3) PNG.
* Normally this array is created
* by reading an image using Class.getResourceAsStream(), but
* the byte array may also be statically stored in a class.
* If the resulting image has a "comment" property that is a string,
* then the string is used as the description of this icon.
*
* @param imageData an array of pixels in an image format supported by
* the AWT Toolkit, such as GIF, JPEG, or (as of 1.3) PNG
* @see java.awt.Toolkit#createImage
* @see #getDescription
* @see java.awt.Image#getProperty
*/
public ImageIcon (byte[] imageData) {
this.image = Toolkit.getDefaultToolkit().createImage(imageData);
if (image == null) {
return;
}
Object o = image.getProperty("comment", imageObserver);
if (o instanceof String) {
description = (String) o;
}
loadImage(image);
}
/**
* Creates an uninitialized image icon.
*/
public ImageIcon() {
}
/**
* Loads the image, returning only when the image is loaded.
* @param image the image
*/
protected void loadImage(Image image) {
synchronized(tracker) {
int id = getNextID();
tracker.addImage(image, id);
try {
tracker.waitForID(id, 0);
} catch (InterruptedException e) {
System.out.println("INTERRUPTED while loading Image");
}
loadStatus = tracker.statusID(id, false);
tracker.removeImage(image, id);
width = image.getWidth(imageObserver);
height = image.getHeight(imageObserver);
}
}
/**
* Returns an ID to use with the MediaTracker in loading an image.
*/
private int getNextID() {
synchronized(tracker) {
return ++mediaTrackerID;
}
}
/**
* Returns the status of the image loading operation.
* @return the loading status as defined by java.awt.MediaTracker
* @see java.awt.MediaTracker#ABORTED
* @see java.awt.MediaTracker#ERRORED
* @see java.awt.MediaTracker#COMPLETE
*/
public int getImageLoadStatus() {
return loadStatus;
}
/**
* Returns this icon's Image
.
* @return the Image
object for this ImageIcon
*/
public Image getImage() {
return image;
}
/**
* Sets the image displayed by this icon.
* @param image the image
*/
public void setImage(Image image) {
this.image = image;
loadImage(image);
}
/**
* Gets the description of the image. This is meant to be a brief
* textual description of the object. For example, it might be
* presented to a blind user to give an indication of the purpose
* of the image.
* The description may be null.
*
* @return a brief textual description of the image
*/
public String getDescription() {
return description;
}
/**
* Sets the description of the image. This is meant to be a brief
* textual description of the object. For example, it might be
* presented to a blind user to give an indication of the purpose
* of the image.
* @param description a brief textual description of the image
*/
public void setDescription(String description) {
this.description = description;
}
/**
* Paints the icon.
* The top-left corner of the icon is drawn at
* the point (x
, y
)
* in the coordinate space of the graphics context g
.
* If this icon has no image observer,
* this method uses the c
component
* as the observer.
*
* @param c the component to be used as the observer
* if this icon has no image observer
* @param g the graphics context
* @param x the X coordinate of the icon's top-left corner
* @param y the Y coordinate of the icon's top-left corner
*/
public synchronized void paintIcon(Component c, Graphics g, int x, int y) {
if(imageObserver == null) {
g.drawImage(image, x, y, c);
} else {
g.drawImage(image, x, y, imageObserver);
}
}
/**
* Gets the width of the icon.
*
* @return the width in pixels of this icon
*/
public int getIconWidth() {
return width;
}
/**
* Gets the height of the icon.
*
* @return the height in pixels of this icon
*/
public int getIconHeight() {
return height;
}
/**
* Sets the image observer for the image. Set this
* property if the ImageIcon contains an animated GIF, so
* the observer is notified to update its display.
* For example:
* * icon = new ImageIcon(...) * button.setIcon(icon); * icon.setImageObserver(button); ** * @param observer the image observer */ public void setImageObserver(ImageObserver observer) { imageObserver = observer; } /** * Returns the image observer for the image. * * @return the image observer, which may be null */ public ImageObserver getImageObserver() { return imageObserver; } /** * Returns a string representation of this image. * * @return a string representing this image */ public String toString() { if (description != null) { return description; } return super.toString(); } private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException { s.defaultReadObject(); int w = s.readInt(); int h = s.readInt(); int[] pixels = (int[])(s.readObject()); if (pixels != null) { Toolkit tk = Toolkit.getDefaultToolkit(); ColorModel cm = ColorModel.getRGBdefault(); image = tk.createImage(new MemoryImageSource(w, h, cm, pixels, 0, w)); loadImage(image); } } private void writeObject(ObjectOutputStream s) throws IOException { s.defaultWriteObject(); int w = getIconWidth(); int h = getIconHeight(); int[] pixels = image != null? new int[w * h] : null; if (image != null) { try { PixelGrabber pg = new PixelGrabber(image, 0, 0, w, h, pixels, 0, w); pg.grabPixels(); if ((pg.getStatus() & ImageObserver.ABORT) != 0) { throw new IOException("failed to load image contents"); } } catch (InterruptedException e) { throw new IOException("image load interrupted"); } } s.writeInt(w); s.writeInt(h); s.writeObject(pixels); } /** * --- Accessibility Support --- */ private AccessibleImageIcon accessibleContext = null; /** * Gets the AccessibleContext associated with this ImageIcon. * For image icons, the AccessibleContext takes the form of an * AccessibleImageIcon. * A new AccessibleImageIcon instance is created if necessary. * * @return an AccessibleImageIcon that serves as the * AccessibleContext of this ImageIcon * @beaninfo * expert: true * description: The AccessibleContext associated with this ImageIcon. */ public AccessibleContext getAccessibleContext() { if (accessibleContext == null) { accessibleContext = new AccessibleImageIcon(); } return accessibleContext; } /** * This class implements accessibility support for the *
ImageIcon
class. It provides an implementation of the
* Java Accessibility API appropriate to image icon user-interface
* elements.
*
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*/
protected class AccessibleImageIcon extends AccessibleContext
implements AccessibleIcon, Serializable {
/*
* AccessibleContest implementation -----------------
*/
/**
* Gets the role of this object.
*
* @return an instance of AccessibleRole describing the role of the
* object
* @see AccessibleRole
*/
public AccessibleRole getAccessibleRole() {
return AccessibleRole.ICON;
}
/**
* Gets the state of this object.
*
* @return an instance of AccessibleStateSet containing the current
* state set of the object
* @see AccessibleState
*/
public AccessibleStateSet getAccessibleStateSet() {
return null;
}
/**
* Gets the Accessible parent of this object. If the parent of this
* object implements Accessible, this method should simply return
* getParent().
*
* @return the Accessible parent of this object -- can be null if this
* object does not have an Accessible parent
*/
public Accessible getAccessibleParent() {
return null;
}
/**
* Gets the index of this object in its accessible parent.
*
* @return the index of this object in its parent; -1 if this
* object does not have an accessible parent.
* @see #getAccessibleParent
*/
public int getAccessibleIndexInParent() {
return -1;
}
/**
* Returns the number of accessible children in the object. If all
* of the children of this object implement Accessible, than this
* method should return the number of children of this object.
*
* @return the number of accessible children in the object.
*/
public int getAccessibleChildrenCount() {
return 0;
}
/**
* Returns the nth Accessible child of the object.
*
* @param i zero-based index of child
* @return the nth Accessible child of the object
*/
public Accessible getAccessibleChild(int i) {
return null;
}
/**
* Returns the locale of this object.
*
* @return the locale of this object
*/
public Locale getLocale() throws IllegalComponentStateException {
return null;
}
/*
* AccessibleIcon implementation -----------------
*/
/**
* Gets the description of the icon. This is meant to be a brief
* textual description of the object. For example, it might be
* presented to a blind user to give an indication of the purpose
* of the icon.
*
* @return the description of the icon
*/
public String getAccessibleIconDescription() {
return ImageIcon.this.getDescription();
}
/**
* Sets the description of the icon. This is meant to be a brief
* textual description of the object. For example, it might be
* presented to a blind user to give an indication of the purpose
* of the icon.
*
* @param description the description of the icon
*/
public void setAccessibleIconDescription(String description) {
ImageIcon.this.setDescription(description);
}
/**
* Gets the height of the icon.
*
* @return the height of the icon
*/
public int getAccessibleIconHeight() {
return ImageIcon.this.height;
}
/**
* Gets the width of the icon.
*
* @return the width of the icon
*/
public int getAccessibleIconWidth() {
return ImageIcon.this.width;
}
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException
{
s.defaultReadObject();
}
private void writeObject(ObjectOutputStream s)
throws IOException
{
s.defaultWriteObject();
}
} // AccessibleImageIcon
}