| /* FilteredImageSource.java -- Java class for providing image data |
| Copyright (C) 1999 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 java.awt.image; |
| |
| import java.util.Hashtable; |
| |
| /** |
| * |
| * @see ImageConsumer |
| * @author C. Brian Jones (cbj@gnu.org) |
| */ |
| public class FilteredImageSource implements ImageProducer |
| { |
| ImageProducer ip; |
| ImageFilter filter; |
| Hashtable consumers = new Hashtable(); |
| |
| /** |
| * The given filter is applied to the given image producer |
| * to create a new image producer. |
| */ |
| public FilteredImageSource(ImageProducer ip, ImageFilter filter) { |
| this.ip = ip; |
| this.filter = filter; |
| } |
| |
| /** |
| * Used to register an <code>ImageConsumer</code> with this |
| * <code>ImageProducer</code>. |
| */ |
| public synchronized void addConsumer(ImageConsumer ic) { |
| if (consumers.containsKey(ic)) |
| return; |
| |
| ImageFilter f = filter.getFilterInstance(ic); |
| consumers.put(ic, f); |
| ip.addConsumer(f); |
| } |
| |
| /** |
| * Used to determine if the given <code>ImageConsumer</code> is |
| * already registered with this <code>ImageProducer</code>. |
| */ |
| public synchronized boolean isConsumer(ImageConsumer ic) { |
| ImageFilter f = (ImageFilter)consumers.get(ic); |
| if (f != null) |
| return ip.isConsumer(f); |
| return false; |
| } |
| |
| /** |
| * Used to remove an <code>ImageConsumer</code> from the list of |
| * registered consumers for this <code>ImageProducer</code>. |
| */ |
| public synchronized void removeConsumer(ImageConsumer ic) { |
| ImageFilter f = (ImageFilter)consumers.remove(ic); |
| if (f != null) |
| ip.removeConsumer(f); |
| } |
| |
| /** |
| * Used to register an <code>ImageConsumer</code> with this |
| * <code>ImageProducer</code> and then immediately start |
| * reconstruction of the image data to be delivered to all |
| * registered consumers. |
| */ |
| public void startProduction(ImageConsumer ic) { |
| ImageFilter f; |
| if (!(consumers.containsKey(ic))) { |
| f = filter.getFilterInstance(ic); |
| consumers.put(ic, f); |
| ip.addConsumer(f); |
| } else { |
| f = (ImageFilter)consumers.get( ic ); |
| } |
| ip.startProduction(f); |
| } |
| |
| /** |
| * Used to register an <code>ImageConsumer</code> with this |
| * <code>ImageProducer</code> and then request that this producer |
| * resend the image data in the order top-down, left-right. |
| */ |
| public void requestTopDownLeftRightResend(ImageConsumer ic) { |
| ImageFilter f = (ImageFilter)consumers.get(ic); |
| ip.requestTopDownLeftRightResend(f); |
| } |
| } |
| |