2006-12-05 Roman Kennke <kennke@aicas.com>

	* gnu/java/awt/peer/gtk/AsyncImage.java: New class. Supports
	asynchronous loading of images.
	* gnu/java/awt/peer/gtk/CairoGraphics2D.java
	(drawImage): Fetch real image from possibly AsyncImage.
	* gnu/java/awt/peer/gtk/ComponentGraphics.java
	(drawImage): Fetch real image from possibly AsyncImage.
	* gnu/java/awt/peer/gtk/GtkToolkit.java
	(createImage(URL)): Create async image.
	(imageOrError): Made method static for easy access from AsyncImage.
	(prepareImage): For async images, register the observer to the
	image.

1 files changed, 257 insertions, 0 deletions

diff --git a/gnu/java/awt/peer/gtk/AsyncImage.java b/gnu/java/awt/peer/gtk/AsyncImage.java
new file mode 100644
index 000000000..855e1d604
--- /dev/null
+++ b/gnu/java/awt/peer/gtk/AsyncImage.java
@@ -0,0 +1,257 @@
+/* AsyncImage.java -- Loads images asynchronously
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.peer.gtk;
+
+import java.awt.Graphics;
+import java.awt.Image;
+import java.awt.image.ImageConsumer;
+import java.awt.image.ImageObserver;
+import java.awt.image.ImageProducer;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+
+/**
+ * Supports asynchronous loading of images.
+ */
+public class AsyncImage
+  extends Image
+{
+
+  /**
+   * Returned as source as long as the image is not complete.
+   */
+  private class NullImageSource
+    implements ImageProducer
+  {
+    private ArrayList consumers;
+
+    NullImageSource()
+    {
+      consumers = new ArrayList();
+    }
+
+    public void addConsumer(ImageConsumer ic)
+    {
+      consumers.add(ic);
+    }
+
+    public boolean isConsumer(ImageConsumer ic)
+    {
+      return consumers.contains(ic);
+    }
+
+    public void removeConsumer(ImageConsumer ic)
+    {
+      consumers.remove(ic);
+    }
+
+    public void requestTopDownLeftRightResend(ImageConsumer ic)
+    {
+      startProduction(ic);
+    }
+
+    public void startProduction(ImageConsumer ic)
+    {
+      consumers.add(ic);
+      for (int i = consumers.size() - 1; i >= 0; i--)
+        {
+          ImageConsumer c = (ImageConsumer) consumers.get(i);
+          c.setDimensions(1, 1);
+          ic.imageComplete(ImageConsumer.SINGLEFRAMEDONE);
+        }
+    }
+    
+  }
+
+  /**
+   * Loads the image asynchronously.
+   */
+  private class Loader
+    implements Runnable
+  {
+    private URL url;
+    Loader(URL u)
+    {
+      url = u;
+    }
+
+    public void run()
+    {
+      Image image;
+      try
+        {
+          GtkImage gtkImage = new GtkImage(url);
+          image = CairoSurface.getBufferedImage(gtkImage);
+        }
+      catch (IllegalArgumentException iae)
+        {
+          image = null;
+        }
+      realImage = GtkToolkit.imageOrError(image);
+      notifyObservers(ImageObserver.ALLBITS | ImageObserver.HEIGHT
+                      | ImageObserver.WIDTH | ImageObserver.PROPERTIES);
+    }
+  }
+
+  /**
+   * The real image. This is null as long as the image is not complete.
+   */
+  Image realImage;
+
+  private HashSet observers;
+
+  /**
+   * Creates a new AsyncImage that loads from the specified URL.
+   */
+  AsyncImage(URL url)
+  {
+    observers = new HashSet();
+    Loader l = new Loader(url);
+    Thread t = new Thread(l);
+    t.start();
+  }
+
+  public void flush()
+  {
+    // Nothing to do here.
+  }
+
+  public Graphics getGraphics()
+  {
+    Image r = realImage;
+    Graphics g = null;
+    if (r != null)
+      g = r.getGraphics(); // Should we return some dummy graphics instead?
+    return g;
+  }
+
+  public int getHeight(ImageObserver observer)
+  {
+    synchronized (observers)
+      {
+        observers.add(observer);
+      }
+    int height = 0;
+    Image r = realImage;
+    if (r != null)
+      height = r.getHeight(observer);
+    return height;
+  }
+
+  public Object getProperty(String name, ImageObserver observer)
+  {
+    synchronized (observers)
+      {
+        observers.add(observer);
+      }
+    Image r = realImage;
+    Object prop = null;
+    if (r != null)
+      prop = r.getProperty(name, observer);
+    return prop;
+  }
+
+  public ImageProducer getSource()
+  {
+    Image r = realImage;
+    ImageProducer source;
+    if (r == null)
+      source = new NullImageSource();
+    else
+      source = r.getSource();
+    return source;
+  }
+
+  public int getWidth(ImageObserver observer)
+  {
+    synchronized (observers)
+      {
+        observers.add(observer);
+      }
+    int width = 0;
+    Image r = realImage;
+    if (r != null)
+      width = r.getWidth(observer);
+    return width;
+  }
+
+  void addObserver(ImageObserver obs)
+  {
+    if (realImage != null && ! observers.contains(obs))
+      {
+        obs.imageUpdate(this, ImageObserver.WIDTH | ImageObserver.HEIGHT
+                        |ImageObserver.ALLBITS | ImageObserver.PROPERTIES,
+                        0, 0, realImage.getWidth(null),
+                        realImage.getHeight(null));
+      }
+    synchronized (observers)
+      {
+        observers.add(obs);
+      }
+  }
+
+  static Image realImage(Image img, ImageObserver obs)
+  {
+    if (img instanceof AsyncImage)
+      {
+        ((AsyncImage) img).addObserver(obs);
+        Image r = ((AsyncImage) img).realImage;
+        if (r != null)
+          img = r;
+      }
+    return img;
+  }
+
+  void notifyObservers(int status)
+  {
+    synchronized (observers)
+      {
+        Image r = realImage;
+        Iterator i = observers.iterator();
+        while (i.hasNext())
+          {
+            ImageObserver obs = (ImageObserver) i.next();
+            obs.imageUpdate(this, status, 0, 0, r.getWidth(null),
+                            r.getHeight(null));
+          }
+      }
+  }
+}