J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2007 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.imageio.event; |
| 27 | |
| 28 | import java.util.EventListener; |
| 29 | import javax.imageio.ImageReader; |
| 30 | |
| 31 | /** |
| 32 | * An interface used by <code>ImageReader</code> implementations to |
| 33 | * notify callers of their image and thumbnail reading methods of |
| 34 | * progress. |
| 35 | * |
| 36 | * <p> This interface receives general indications of decoding |
| 37 | * progress (via the <code>imageProgress</code> and |
| 38 | * <code>thumbnailProgress</code> methods), and events indicating when |
| 39 | * an entire image has been updated (via the |
| 40 | * <code>imageStarted</code>, <code>imageComplete</code>, |
| 41 | * <code>thumbnailStarted</code> and <code>thumbnailComplete</code> |
| 42 | * methods). Applications that wish to be informed of pixel updates |
| 43 | * as they happen (for example, during progressive decoding), should |
| 44 | * provide an <code>IIOReadUpdateListener</code>. |
| 45 | * |
| 46 | * @see IIOReadUpdateListener |
| 47 | * @see javax.imageio.ImageReader#addIIOReadProgressListener |
| 48 | * @see javax.imageio.ImageReader#removeIIOReadProgressListener |
| 49 | * |
| 50 | */ |
| 51 | public interface IIOReadProgressListener extends EventListener { |
| 52 | |
| 53 | /** |
| 54 | * Reports that a sequence of read operations is beginning. |
| 55 | * <code>ImageReader</code> implementations are required to call |
| 56 | * this method exactly once from their |
| 57 | * <code>readAll(Iterator)</code> method. |
| 58 | * |
| 59 | * @param source the <code>ImageReader</code> object calling this method. |
| 60 | * @param minIndex the index of the first image to be read. |
| 61 | */ |
| 62 | void sequenceStarted(ImageReader source, int minIndex); |
| 63 | |
| 64 | /** |
| 65 | * Reports that a sequence of read operationshas completed. |
| 66 | * <code>ImageReader</code> implementations are required to call |
| 67 | * this method exactly once from their |
| 68 | * <code>readAll(Iterator)</code> method. |
| 69 | * |
| 70 | * @param source the <code>ImageReader</code> object calling this method. |
| 71 | */ |
| 72 | void sequenceComplete(ImageReader source); |
| 73 | |
| 74 | /** |
| 75 | * Reports that an image read operation is beginning. All |
| 76 | * <code>ImageReader</code> implementations are required to call |
| 77 | * this method exactly once when beginning an image read |
| 78 | * operation. |
| 79 | * |
| 80 | * @param source the <code>ImageReader</code> object calling this method. |
| 81 | * @param imageIndex the index of the image being read within its |
| 82 | * containing input file or stream. |
| 83 | */ |
| 84 | void imageStarted(ImageReader source, int imageIndex); |
| 85 | |
| 86 | /** |
| 87 | * Reports the approximate degree of completion of the current |
| 88 | * <code>read</code> call of the associated |
| 89 | * <code>ImageReader</code>. |
| 90 | * |
| 91 | * <p> The degree of completion is expressed as a percentage |
| 92 | * varying from <code>0.0F</code> to <code>100.0F</code>. The |
| 93 | * percentage should ideally be calculated in terms of the |
| 94 | * remaining time to completion, but it is usually more practical |
| 95 | * to use a more well-defined metric such as pixels decoded or |
| 96 | * portion of input stream consumed. In any case, a sequence of |
| 97 | * calls to this method during a given read operation should |
| 98 | * supply a monotonically increasing sequence of percentage |
| 99 | * values. It is not necessary to supply the exact values |
| 100 | * <code>0</code> and <code>100</code>, as these may be inferred |
| 101 | * by the callee from other methods. |
| 102 | * |
| 103 | * <p> Each particular <code>ImageReader</code> implementation may |
| 104 | * call this method at whatever frequency it desires. A rule of |
| 105 | * thumb is to call it around each 5 percent mark. |
| 106 | * |
| 107 | * @param source the <code>ImageReader</code> object calling this method. |
| 108 | * @param percentageDone the approximate percentage of decoding that |
| 109 | * has been completed. |
| 110 | */ |
| 111 | void imageProgress(ImageReader source, float percentageDone); |
| 112 | |
| 113 | /** |
| 114 | * Reports that the current image read operation has completed. |
| 115 | * All <code>ImageReader</code> implementations are required to |
| 116 | * call this method exactly once upon completion of each image |
| 117 | * read operation. |
| 118 | * |
| 119 | * @param source the <code>ImageReader</code> object calling this |
| 120 | * method. |
| 121 | */ |
| 122 | void imageComplete(ImageReader source); |
| 123 | |
| 124 | /** |
| 125 | * Reports that a thumbnail read operation is beginning. All |
| 126 | * <code>ImageReader</code> implementations are required to call |
| 127 | * this method exactly once when beginning a thumbnail read |
| 128 | * operation. |
| 129 | * |
| 130 | * @param source the <code>ImageReader</code> object calling this method. |
| 131 | * @param imageIndex the index of the image being read within its |
| 132 | * containing input file or stream. |
| 133 | * @param thumbnailIndex the index of the thumbnail being read. |
| 134 | */ |
| 135 | void thumbnailStarted(ImageReader source, |
| 136 | int imageIndex, int thumbnailIndex); |
| 137 | |
| 138 | /** |
| 139 | * Reports the approximate degree of completion of the current |
| 140 | * <code>getThumbnail</code> call within the associated |
| 141 | * <code>ImageReader</code>. The semantics are identical to those |
| 142 | * of <code>imageProgress</code>. |
| 143 | * |
| 144 | * @param source the <code>ImageReader</code> object calling this method. |
| 145 | * @param percentageDone the approximate percentage of decoding that |
| 146 | * has been completed. |
| 147 | */ |
| 148 | void thumbnailProgress(ImageReader source, float percentageDone); |
| 149 | |
| 150 | /** |
| 151 | * Reports that a thumbnail read operation has completed. All |
| 152 | * <code>ImageReader</code> implementations are required to call |
| 153 | * this method exactly once upon completion of each thumbnail read |
| 154 | * operation. |
| 155 | * |
| 156 | * @param source the <code>ImageReader</code> object calling this |
| 157 | * method. |
| 158 | */ |
| 159 | void thumbnailComplete(ImageReader source); |
| 160 | |
| 161 | /** |
| 162 | * Reports that a read has been aborted via the reader's |
| 163 | * <code>abort</code> method. No further notifications will be |
| 164 | * given. |
| 165 | * |
| 166 | * @param source the <code>ImageReader</code> object calling this |
| 167 | * method. |
| 168 | */ |
| 169 | void readAborted(ImageReader source); |
| 170 | } |