001/* ImageProducer.java -- Java interface for image production
002   Copyright (C) 1999 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.awt.image;
040
041/**
042 * An object implementing the <code>ImageProducer</code> interface can
043 * produce data for images.  Each image has a corresponding
044 * <code>ImageProducer</code> which is needed for things such as
045 * resizing the image.
046 *
047 * @see ImageConsumer
048 * @author C. Brian Jones (cbj@gnu.org) 
049 */
050public interface ImageProducer
051{
052    /**
053     * Used to register an <code>ImageConsumer</code> with this
054     * <code>ImageProducer</code>.  
055     */
056    void addConsumer(ImageConsumer ic);
057
058    /**
059     * Used to determine if the given <code>ImageConsumer</code> is
060     * already registered with this <code>ImageProducer</code>.  
061     */
062    boolean isConsumer(ImageConsumer ic);
063
064    /**
065     * Used to remove an <code>ImageConsumer</code> from the list of
066     * registered consumers for this <code>ImageProducer</code>.  
067     */
068    void removeConsumer(ImageConsumer ic);
069
070    /**
071     * Used to register an <code>ImageConsumer</code> with this
072     * <code>ImageProducer</code> and then immediately start
073     * reconstruction of the image data to be delivered to all
074     * registered consumers.  
075     */
076    void startProduction(ImageConsumer ic);
077
078    /**
079     * Used to register an <code>ImageConsumer</code> with this
080     * <code>ImageProducer</code> and then request that this producer
081     * resend the image data in the order top-down, left-right.  
082     */
083    void requestTopDownLeftRightResend(ImageConsumer ic);
084}
085