Source for java.awt.image.ImageObserver

   1: /* ImageObserver.java -- Java interface for asynchronous updates to an image
   2:    Copyright (C) 1999 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package java.awt.image;
  40: 
  41: import java.awt.Image;
  42: 
  43: /**
  44:  * An object implementing the <code>ImageObserver</code> interface can
  45:  * receive updates on image construction from an
  46:  * <code>ImageProducer</code> asynchronously.
  47:  *
  48:  * @see ImageProducer
  49:  * @author C. Brian Jones (cbj@gnu.org) 
  50:  */
  51: public interface ImageObserver
  52: {
  53:     /**
  54:      * The width of the image has been provided as the
  55:      * <code>width</code> argument to <code>imageUpdate</code>.
  56:      *
  57:      * @see #imageUpdate 
  58:      */
  59:     int WIDTH = 1;
  60: 
  61:     /**
  62:      * The height of the image has been provided as the
  63:      * <code>height</code> argument to <code>imageUpdate</code>.
  64:      *
  65:      * @see #imageUpdate 
  66:      */
  67:     int HEIGHT = 2;
  68: 
  69:     /**
  70:      * The properties of the image have been provided.
  71:      *
  72:      * @see #imageUpdate
  73:      * @see java.awt.Image#getProperty (java.lang.String, java.awt.image.ImageObserver)
  74:      */
  75:     int PROPERTIES = 4;
  76: 
  77:     /**
  78:      * More pixels are now available for drawing a scaled variation of
  79:      * the image.
  80:      *
  81:      * @see #imageUpdate 
  82:      */
  83:     int SOMEBITS = 8;
  84: 
  85:     /**
  86:      * All the pixels needed to draw a complete frame of a multi-frame
  87:      * image are available.
  88:      *
  89:      * @see #imageUpdate 
  90:      */
  91:     int FRAMEBITS = 16;
  92: 
  93:     /**
  94:      * An image with a single frame, a static image, is complete.
  95:      *
  96:      * @see #imageUpdate
  97:      */
  98:     int ALLBITS = 32;
  99: 
 100:     /**
 101:      * An error was encountered while producing the image.
 102:      *
 103:      * @see #imageUpdate
 104:      */
 105:     int ERROR = 64;
 106: 
 107:     /**
 108:      * Production of the image was aborted.
 109:      *
 110:      * @see #imageUpdate
 111:      */
 112:     int ABORT = 128;
 113: 
 114:     /**
 115:      * This is a callback method for an asynchronous image producer to
 116:      * provide updates on the production of the image as it happens.
 117:      *
 118:      * @param image the image the update refers to
 119:      * @param flags a bit mask indicating what is provided with this update
 120:      * @param x the x coordinate of the image
 121:      * @param y the y coordinate of the image
 122:      * @param width the width of the image
 123:      * @param height the height of the image
 124:      * 
 125:      * @see java.awt.Image 
 126:      */
 127:     boolean imageUpdate(Image image, int flags, int x, 
 128:                     int y, int width, int height);
 129: }