1 /*
2 * Copyright (c) 2000, 2014, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javax.imageio;
27
28 import java.awt.Dimension;
29 import java.util.Locale;
30
31 /**
32 * A class describing how a stream is to be encoded. Instances of
33 * this class or its subclasses are used to supply prescriptive
34 * "how-to" information to instances of <code>ImageWriter</code>.
35 *
36 * <p> A plug-in for a specific image format may define a subclass of
37 * this class, and return objects of that class from the
38 * <code>getDefaultWriteParam</code> method of its
39 * <code>ImageWriter</code> implementation. For example, the built-in
40 * JPEG writer plug-in will return instances of
41 * <code>javax.imageio.plugins.jpeg.JPEGImageWriteParam</code>.
42 *
43 * <p> The region of the image to be written is determined by first
44 * intersecting the actual bounds of the image with the rectangle
45 * specified by <code>IIOParam.setSourceRegion</code>, if any. If the
46 * resulting rectangle has a width or height of zero, the writer will
47 * throw an <code>IIOException</code>. If the intersection is
48 * non-empty, writing will commence with the first subsampled pixel
49 * and include additional pixels within the intersected bounds
50 * according to the horizontal and vertical subsampling factors
51 * specified by {@link IIOParam#setSourceSubsampling
52 * IIOParam.setSourceSubsampling}.
53 *
54 * <p> Individual features such as tiling, progressive encoding, and
55 * compression may be set in one of four modes.
56 * <code>MODE_DISABLED</code> disables the features;
57 * <code>MODE_DEFAULT</code> enables the feature with
58 * writer-controlled parameter values; <code>MODE_EXPLICIT</code>
59 * enables the feature and allows the use of a <code>set</code> method
60 * to provide additional parameters; and
61 * <code>MODE_COPY_FROM_METADATA</code> copies relevant parameter
62 * values from the stream and image metadata objects passed to the
63 * writer. The default for all features is
64 * <code>MODE_COPY_FROM_METADATA</code>. Non-standard features
65 * supplied in subclasses are encouraged, but not required to use a
66 * similar scheme.
67 *
68 * <p> Plug-in writers may extend the functionality of
69 * <code>ImageWriteParam</code> by providing a subclass that implements
70 * additional, plug-in specific interfaces. It is up to the plug-in
71 * to document what interfaces are available and how they are to be
72 * used. Writers will silently ignore any extended features of an
73 * <code>ImageWriteParam</code> subclass of which they are not aware.
74 * Also, they may ignore any optional features that they normally
75 * disable when creating their own <code>ImageWriteParam</code>
76 * instances via <code>getDefaultWriteParam</code>.
77 *
78 * <p> Note that unless a query method exists for a capability, it must
79 * be supported by all <code>ImageWriter</code> implementations
80 * (<i>e.g.</i> progressive encoding is optional, but subsampling must be
81 * supported).
82 *
83 *
84 * @see ImageReadParam
85 */
86 public class ImageWriteParam extends IIOParam {
87
88 /**
89 * A constant value that may be passed into methods such as
90 * <code>setTilingMode</code>, <code>setProgressiveMode</code>,
91 * and <code>setCompressionMode</code> to disable a feature for
92 * future writes. That is, when this mode is set the stream will
93 * <b>not</b> be tiled, progressive, or compressed, and the
94 * relevant accessor methods will throw an
95 * <code>IllegalStateException</code>.
96 *
97 * @see #MODE_EXPLICIT
98 * @see #MODE_COPY_FROM_METADATA
99 * @see #MODE_DEFAULT
100 * @see #setProgressiveMode
101 * @see #getProgressiveMode
102 * @see #setTilingMode
103 * @see #getTilingMode
104 * @see #setCompressionMode
105 * @see #getCompressionMode
106 */
107 public static final int MODE_DISABLED = 0;
108
109 /**
110 * A constant value that may be passed into methods such as
111 * <code>setTilingMode</code>,
112 * <code>setProgressiveMode</code>, and
113 * <code>setCompressionMode</code> to enable that feature for
114 * future writes. That is, when this mode is enabled the stream
115 * will be tiled, progressive, or compressed according to a
116 * sensible default chosen internally by the writer in a plug-in
117 * dependent way, and the relevant accessor methods will
118 * throw an <code>IllegalStateException</code>.
119 *
120 * @see #MODE_DISABLED
121 * @see #MODE_EXPLICIT
122 * @see #MODE_COPY_FROM_METADATA
123 * @see #setProgressiveMode
124 * @see #getProgressiveMode
125 * @see #setTilingMode
126 * @see #getTilingMode
127 * @see #setCompressionMode
128 * @see #getCompressionMode
129 */
130 public static final int MODE_DEFAULT = 1;
131
132 /**
133 * A constant value that may be passed into methods such as
134 * <code>setTilingMode</code> or <code>setCompressionMode</code>
135 * to enable a feature for future writes. That is, when this mode
136 * is set the stream will be tiled or compressed according to
137 * additional information supplied to the corresponding
138 * <code>set</code> methods in this class and retrievable from the
139 * corresponding <code>get</code> methods. Note that this mode is
140 * not supported for progressive output.
141 *
142 * @see #MODE_DISABLED
143 * @see #MODE_COPY_FROM_METADATA
144 * @see #MODE_DEFAULT
145 * @see #setProgressiveMode
146 * @see #getProgressiveMode
147 * @see #setTilingMode
148 * @see #getTilingMode
149 * @see #setCompressionMode
150 * @see #getCompressionMode
151 */
152 public static final int MODE_EXPLICIT = 2;
153
154 /**
155 * A constant value that may be passed into methods such as
156 * <code>setTilingMode</code>, <code>setProgressiveMode</code>, or
157 * <code>setCompressionMode</code> to enable that feature for
158 * future writes. That is, when this mode is enabled the stream
159 * will be tiled, progressive, or compressed based on the contents
160 * of stream and/or image metadata passed into the write
161 * operation, and any relevant accessor methods will throw an
162 * <code>IllegalStateException</code>.
163 *
164 * <p> This is the default mode for all features, so that a read
165 * including metadata followed by a write including metadata will
166 * preserve as much information as possible.
167 *
168 * @see #MODE_DISABLED
169 * @see #MODE_EXPLICIT
170 * @see #MODE_DEFAULT
171 * @see #setProgressiveMode
172 * @see #getProgressiveMode
173 * @see #setTilingMode
174 * @see #getTilingMode
175 * @see #setCompressionMode
176 * @see #getCompressionMode
177 */
178 public static final int MODE_COPY_FROM_METADATA = 3;
179
180 // If more modes are added, this should be updated.
181 private static final int MAX_MODE = MODE_COPY_FROM_METADATA;
182
183 /**
184 * A <code>boolean</code> that is <code>true</code> if this
185 * <code>ImageWriteParam</code> allows tile width and tile height
186 * parameters to be set. By default, the value is
187 * <code>false</code>. Subclasses must set the value manually.
188 *
189 * <p> Subclasses that do not support writing tiles should ensure
190 * that this value is set to <code>false</code>.
191 */
192 protected boolean canWriteTiles = false;
193
194 /**
195 * The mode controlling tiling settings, which Must be
196 * set to one of the four <code>MODE_*</code> values. The default
197 * is <code>MODE_COPY_FROM_METADATA</code>.
198 *
199 * <p> Subclasses that do not writing tiles may ignore this value.
200 *
201 * @see #MODE_DISABLED
202 * @see #MODE_EXPLICIT
203 * @see #MODE_COPY_FROM_METADATA
204 * @see #MODE_DEFAULT
205 * @see #setTilingMode
206 * @see #getTilingMode
207 */
208 protected int tilingMode = MODE_COPY_FROM_METADATA;
209
210 /**
211 * An array of preferred tile size range pairs. The default value
212 * is <code>null</code>, which indicates that there are no
213 * preferred sizes. If the value is non-<code>null</code>, it
214 * must have an even length of at least two.
215 *
216 * <p> Subclasses that do not support writing tiles may ignore
217 * this value.
218 *
219 * @see #getPreferredTileSizes
220 */
221 protected Dimension[] preferredTileSizes = null;
222
223 /**
224 * A <code>boolean</code> that is <code>true</code> if tiling
225 * parameters have been specified.
226 *
227 * <p> Subclasses that do not support writing tiles may ignore
228 * this value.
229 */
230 protected boolean tilingSet = false;
231
232 /**
233 * The width of each tile if tiling has been set, or 0 otherwise.
234 *
235 * <p> Subclasses that do not support tiling may ignore this
236 * value.
237 */
238 protected int tileWidth = 0;
239
240 /**
241 * The height of each tile if tiling has been set, or 0 otherwise.
242 * The initial value is <code>0</code>.
243 *
244 * <p> Subclasses that do not support tiling may ignore this
245 * value.
246 */
247 protected int tileHeight = 0;
248
249 /**
250 * A <code>boolean</code> that is <code>true</code> if this
251 * <code>ImageWriteParam</code> allows tiling grid offset
252 * parameters to be set. By default, the value is
253 * <code>false</code>. Subclasses must set the value manually.
254 *
255 * <p> Subclasses that do not support writing tiles, or that
256 * support writing but not offsetting tiles must ensure that this
257 * value is set to <code>false</code>.
258 */
259 protected boolean canOffsetTiles = false;
260
261 /**
262 * The amount by which the tile grid origin should be offset
263 * horizontally from the image origin if tiling has been set,
264 * or 0 otherwise. The initial value is <code>0</code>.
265 *
266 * <p> Subclasses that do not support offsetting tiles may ignore
267 * this value.
268 */
269 protected int tileGridXOffset = 0;
270
271 /**
272 * The amount by which the tile grid origin should be offset
273 * vertically from the image origin if tiling has been set,
274 * or 0 otherwise. The initial value is <code>0</code>.
275 *
276 * <p> Subclasses that do not support offsetting tiles may ignore
277 * this value.
278 */
279 protected int tileGridYOffset = 0;
280
281 /**
282 * A <code>boolean</code> that is <code>true</code> if this
283 * <code>ImageWriteParam</code> allows images to be written as a
284 * progressive sequence of increasing quality passes. By default,
285 * the value is <code>false</code>. Subclasses must set the value
286 * manually.
287 *
288 * <p> Subclasses that do not support progressive encoding must
289 * ensure that this value is set to <code>false</code>.
290 */
291 protected boolean canWriteProgressive = false;
292
293 /**
294 * The mode controlling progressive encoding, which must be set to
295 * one of the four <code>MODE_*</code> values, except
296 * <code>MODE_EXPLICIT</code>. The default is
297 * <code>MODE_COPY_FROM_METADATA</code>.
298 *
299 * <p> Subclasses that do not support progressive encoding may
300 * ignore this value.
301 *
302 * @see #MODE_DISABLED
303 * @see #MODE_EXPLICIT
304 * @see #MODE_COPY_FROM_METADATA
305 * @see #MODE_DEFAULT
306 * @see #setProgressiveMode
307 * @see #getProgressiveMode
308 */
309 protected int progressiveMode = MODE_COPY_FROM_METADATA;
310
311 /**
312 * A <code>boolean</code> that is <code>true</code> if this writer
313 * can write images using compression. By default, the value is
314 * <code>false</code>. Subclasses must set the value manually.
315 *
316 * <p> Subclasses that do not support compression must ensure that
317 * this value is set to <code>false</code>.
318 */
319 protected boolean canWriteCompressed = false;
320
321 /**
322 * The mode controlling compression settings, which must be set to
323 * one of the four <code>MODE_*</code> values. The default is
324 * <code>MODE_COPY_FROM_METADATA</code>.
325 *
326 * <p> Subclasses that do not support compression may ignore this
327 * value.
328 *
329 * @see #MODE_DISABLED
330 * @see #MODE_EXPLICIT
331 * @see #MODE_COPY_FROM_METADATA
332 * @see #MODE_DEFAULT
333 * @see #setCompressionMode
334 * @see #getCompressionMode
335 */
336 protected int compressionMode = MODE_COPY_FROM_METADATA;
337
338 /**
339 * An array of <code>String</code>s containing the names of the
340 * available compression types. Subclasses must set the value
341 * manually.
342 *
343 * <p> Subclasses that do not support compression may ignore this
344 * value.
345 */
346 protected String[] compressionTypes = null;
347
348 /**
349 * A <code>String</code> containing the name of the current
350 * compression type, or <code>null</code> if none is set.
351 *
352 * <p> Subclasses that do not support compression may ignore this
353 * value.
354 */
355 protected String compressionType = null;
356
357 /**
358 * A <code>float</code> containing the current compression quality
359 * setting. The initial value is <code>1.0F</code>.
360 *
361 * <p> Subclasses that do not support compression may ignore this
362 * value.
363 */
364 protected float compressionQuality = 1.0F;
365
366 /**
367 * A <code>Locale</code> to be used to localize compression type
368 * names and quality descriptions, or <code>null</code> to use a
369 * default <code>Locale</code>. Subclasses must set the value
370 * manually.
371 */
372 protected Locale locale = null;
373
374 /**
375 * Constructs an empty <code>ImageWriteParam</code>. It is up to
376 * the subclass to set up the instance variables properly.
377 */
378 protected ImageWriteParam() {}
379
380 /**
381 * Constructs an <code>ImageWriteParam</code> set to use a
382 * given <code>Locale</code>.
383 *
384 * @param locale a <code>Locale</code> to be used to localize
385 * compression type names and quality descriptions, or
386 * <code>null</code>.
387 */
388 public ImageWriteParam(Locale locale) {
389 this.locale = locale;
390 }
391
392 // Return a deep copy of the array
393 private static Dimension[] clonePreferredTileSizes(Dimension[] sizes) {
394 if (sizes == null) {
395 return null;
396 }
397 Dimension[] temp = new Dimension[sizes.length];
398 for (int i = 0; i < sizes.length; i++) {
399 temp[i] = new Dimension(sizes[i]);
400 }
401 return temp;
402 }
403
404 /**
405 * Returns the currently set <code>Locale</code>, or
406 * <code>null</code> if only a default <code>Locale</code> is
407 * supported.
408 *
409 * @return the current <code>Locale</code>, or <code>null</code>.
410 */
411 public Locale getLocale() {
412 return locale;
413 }
414
415 /**
416 * Returns <code>true</code> if the writer can perform tiling
417 * while writing. If this method returns <code>false</code>, then
418 * <code>setTiling</code> will throw an
419 * <code>UnsupportedOperationException</code>.
420 *
421 * @return <code>true</code> if the writer supports tiling.
422 *
423 * @see #canOffsetTiles()
424 * @see #setTiling(int, int, int, int)
425 */
426 public boolean canWriteTiles() {
427 return canWriteTiles;
428 }
429
430 /**
431 * Returns <code>true</code> if the writer can perform tiling with
432 * non-zero grid offsets while writing. If this method returns
433 * <code>false</code>, then <code>setTiling</code> will throw an
434 * <code>UnsupportedOperationException</code> if the grid offset
435 * arguments are not both zero. If <code>canWriteTiles</code>
436 * returns <code>false</code>, this method will return
437 * <code>false</code> as well.
438 *
439 * @return <code>true</code> if the writer supports non-zero tile
440 * offsets.
441 *
442 * @see #canWriteTiles()
443 * @see #setTiling(int, int, int, int)
444 */
445 public boolean canOffsetTiles() {
446 return canOffsetTiles;
447 }
448
449 /**
450 * Determines whether the image will be tiled in the output
451 * stream and, if it will, how the tiling parameters will be
452 * determined. The modes are interpreted as follows:
453 *
454 * <ul>
455 *
456 * <li><code>MODE_DISABLED</code> - The image will not be tiled.
457 * <code>setTiling</code> will throw an
458 * <code>IllegalStateException</code>.
459 *
460 * <li><code>MODE_DEFAULT</code> - The image will be tiled using
461 * default parameters. <code>setTiling</code> will throw an
462 * <code>IllegalStateException</code>.
463 *
464 * <li><code>MODE_EXPLICIT</code> - The image will be tiled
465 * according to parameters given in the {@link #setTiling setTiling}
466 * method. Any previously set tiling parameters are discarded.
467 *
468 * <li><code>MODE_COPY_FROM_METADATA</code> - The image will
469 * conform to the metadata object passed in to a write.
470 * <code>setTiling</code> will throw an
471 * <code>IllegalStateException</code>.
472 *
473 * </ul>
474 *
475 * @param mode The mode to use for tiling.
476 *
477 * @exception UnsupportedOperationException if
478 * <code>canWriteTiles</code> returns <code>false</code>.
479 * @exception IllegalArgumentException if <code>mode</code> is not
480 * one of the modes listed above.
481 *
482 * @see #setTiling
483 * @see #getTilingMode
484 */
485 public void setTilingMode(int mode) {
486 if (canWriteTiles() == false) {
487 throw new UnsupportedOperationException("Tiling not supported!");
488 }
489 if (mode < MODE_DISABLED || mode > MAX_MODE) {
490 throw new IllegalArgumentException("Illegal value for mode!");
491 }
492 this.tilingMode = mode;
493 if (mode == MODE_EXPLICIT) {
494 unsetTiling();
495 }
496 }
497
498 /**
499 * Returns the current tiling mode, if tiling is supported.
500 * Otherwise throws an <code>UnsupportedOperationException</code>.
501 *
502 * @return the current tiling mode.
503 *
504 * @exception UnsupportedOperationException if
505 * <code>canWriteTiles</code> returns <code>false</code>.
506 *
507 * @see #setTilingMode
508 */
509 public int getTilingMode() {
510 if (!canWriteTiles()) {
511 throw new UnsupportedOperationException("Tiling not supported");
512 }
513 return tilingMode;
514 }
515
516 /**
517 * Returns an array of <code>Dimension</code>s indicating the
518 * legal size ranges for tiles as they will be encoded in the
519 * output file or stream. The returned array is a copy.
520 *
521 * <p> The information is returned as a set of pairs; the first
522 * element of a pair contains an (inclusive) minimum width and
523 * height, and the second element contains an (inclusive) maximum
524 * width and height. Together, each pair defines a valid range of
525 * sizes. To specify a fixed size, use the same width and height
526 * for both elements. To specify an arbitrary range, a value of
527 * <code>null</code> is used in place of an actual array of
528 * <code>Dimension</code>s.
529 *
530 * <p> If no array is specified on the constructor, but tiling is
531 * allowed, then this method returns <code>null</code>.
532 *
533 * @exception UnsupportedOperationException if the plug-in does
534 * not support tiling.
535 *
536 * @return an array of <code>Dimension</code>s with an even length
537 * of at least two, or <code>null</code>.
538 */
539 public Dimension[] getPreferredTileSizes() {
540 if (!canWriteTiles()) {
541 throw new UnsupportedOperationException("Tiling not supported");
542 }
543 return clonePreferredTileSizes(preferredTileSizes);
544 }
545
546 /**
547 * Specifies that the image should be tiled in the output stream.
548 * The <code>tileWidth</code> and <code>tileHeight</code>
549 * parameters specify the width and height of the tiles in the
550 * file. If the tile width or height is greater than the width or
551 * height of the image, the image is not tiled in that dimension.
552 *
553 * <p> If <code>canOffsetTiles</code> returns <code>false</code>,
554 * then the <code>tileGridXOffset</code> and
555 * <code>tileGridYOffset</code> parameters must be zero.
556 *
557 * @param tileWidth the width of each tile.
558 * @param tileHeight the height of each tile.
559 * @param tileGridXOffset the horizontal offset of the tile grid.
560 * @param tileGridYOffset the vertical offset of the tile grid.
561 *
562 * @exception UnsupportedOperationException if the plug-in does not
563 * support tiling.
564 * @exception IllegalStateException if the tiling mode is not
565 * <code>MODE_EXPLICIT</code>.
566 * @exception UnsupportedOperationException if the plug-in does not
567 * support grid offsets, and the grid offsets are not both zero.
568 * @exception IllegalArgumentException if the tile size is not
569 * within one of the allowable ranges returned by
570 * <code>getPreferredTileSizes</code>.
571 * @exception IllegalArgumentException if <code>tileWidth</code>
572 * or <code>tileHeight</code> is less than or equal to 0.
573 *
574 * @see #canWriteTiles
575 * @see #canOffsetTiles
576 * @see #getTileWidth()
577 * @see #getTileHeight()
578 * @see #getTileGridXOffset()
579 * @see #getTileGridYOffset()
580 */
581 public void setTiling(int tileWidth,
582 int tileHeight,
583 int tileGridXOffset,
584 int tileGridYOffset) {
585 if (!canWriteTiles()) {
586 throw new UnsupportedOperationException("Tiling not supported!");
587 }
588 if (getTilingMode() != MODE_EXPLICIT) {
589 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
590 }
591 if (tileWidth <= 0 || tileHeight <= 0) {
592 throw new IllegalArgumentException
593 ("tile dimensions are non-positive!");
594 }
595 boolean tilesOffset = (tileGridXOffset != 0) || (tileGridYOffset != 0);
596 if (!canOffsetTiles() && tilesOffset) {
597 throw new UnsupportedOperationException("Can't offset tiles!");
598 }
599 if (preferredTileSizes != null) {
600 boolean ok = true;
601 for (int i = 0; i < preferredTileSizes.length; i += 2) {
602 Dimension min = preferredTileSizes[i];
603 Dimension max = preferredTileSizes[i+1];
604 if ((tileWidth < min.width) ||
605 (tileWidth > max.width) ||
606 (tileHeight < min.height) ||
607 (tileHeight > max.height)) {
608 ok = false;
609 break;
610 }
611 }
612 if (!ok) {
613 throw new IllegalArgumentException("Illegal tile size!");
614 }
615 }
616
617 this.tilingSet = true;
618 this.tileWidth = tileWidth;
619 this.tileHeight = tileHeight;
620 this.tileGridXOffset = tileGridXOffset;
621 this.tileGridYOffset = tileGridYOffset;
622 }
623
624 /**
625 * Removes any previous tile grid parameters specified by calls to
626 * <code>setTiling</code>.
627 *
628 * <p> The default implementation sets the instance variables
629 * <code>tileWidth</code>, <code>tileHeight</code>,
630 * <code>tileGridXOffset</code>, and
631 * <code>tileGridYOffset</code> to <code>0</code>.
632 *
633 * @exception UnsupportedOperationException if the plug-in does not
634 * support tiling.
635 * @exception IllegalStateException if the tiling mode is not
636 * <code>MODE_EXPLICIT</code>.
637 *
638 * @see #setTiling(int, int, int, int)
639 */
640 public void unsetTiling() {
641 if (!canWriteTiles()) {
642 throw new UnsupportedOperationException("Tiling not supported!");
643 }
644 if (getTilingMode() != MODE_EXPLICIT) {
645 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
646 }
647 this.tilingSet = false;
648 this.tileWidth = 0;
649 this.tileHeight = 0;
650 this.tileGridXOffset = 0;
651 this.tileGridYOffset = 0;
652 }
653
654 /**
655 * Returns the width of each tile in an image as it will be
656 * written to the output stream. If tiling parameters have not
657 * been set, an <code>IllegalStateException</code> is thrown.
658 *
659 * @return the tile width to be used for encoding.
660 *
661 * @exception UnsupportedOperationException if the plug-in does not
662 * support tiling.
663 * @exception IllegalStateException if the tiling mode is not
664 * <code>MODE_EXPLICIT</code>.
665 * @exception IllegalStateException if the tiling parameters have
666 * not been set.
667 *
668 * @see #setTiling(int, int, int, int)
669 * @see #getTileHeight()
670 */
671 public int getTileWidth() {
672 if (!canWriteTiles()) {
673 throw new UnsupportedOperationException("Tiling not supported!");
674 }
675 if (getTilingMode() != MODE_EXPLICIT) {
676 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
677 }
678 if (!tilingSet) {
679 throw new IllegalStateException("Tiling parameters not set!");
680 }
681 return tileWidth;
682 }
683
684 /**
685 * Returns the height of each tile in an image as it will be written to
686 * the output stream. If tiling parameters have not
687 * been set, an <code>IllegalStateException</code> is thrown.
688 *
689 * @return the tile height to be used for encoding.
690 *
691 * @exception UnsupportedOperationException if the plug-in does not
692 * support tiling.
693 * @exception IllegalStateException if the tiling mode is not
694 * <code>MODE_EXPLICIT</code>.
695 * @exception IllegalStateException if the tiling parameters have
696 * not been set.
697 *
698 * @see #setTiling(int, int, int, int)
699 * @see #getTileWidth()
700 */
701 public int getTileHeight() {
702 if (!canWriteTiles()) {
703 throw new UnsupportedOperationException("Tiling not supported!");
704 }
705 if (getTilingMode() != MODE_EXPLICIT) {
706 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
707 }
708 if (!tilingSet) {
709 throw new IllegalStateException("Tiling parameters not set!");
710 }
711 return tileHeight;
712 }
713
714 /**
715 * Returns the horizontal tile grid offset of an image as it will
716 * be written to the output stream. If tiling parameters have not
717 * been set, an <code>IllegalStateException</code> is thrown.
718 *
719 * @return the tile grid X offset to be used for encoding.
720 *
721 * @exception UnsupportedOperationException if the plug-in does not
722 * support tiling.
723 * @exception IllegalStateException if the tiling mode is not
724 * <code>MODE_EXPLICIT</code>.
725 * @exception IllegalStateException if the tiling parameters have
726 * not been set.
727 *
728 * @see #setTiling(int, int, int, int)
729 * @see #getTileGridYOffset()
730 */
731 public int getTileGridXOffset() {
732 if (!canWriteTiles()) {
733 throw new UnsupportedOperationException("Tiling not supported!");
734 }
735 if (getTilingMode() != MODE_EXPLICIT) {
736 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
737 }
738 if (!tilingSet) {
739 throw new IllegalStateException("Tiling parameters not set!");
740 }
741 return tileGridXOffset;
742 }
743
744 /**
745 * Returns the vertical tile grid offset of an image as it will
746 * be written to the output stream. If tiling parameters have not
747 * been set, an <code>IllegalStateException</code> is thrown.
748 *
749 * @return the tile grid Y offset to be used for encoding.
750 *
751 * @exception UnsupportedOperationException if the plug-in does not
752 * support tiling.
753 * @exception IllegalStateException if the tiling mode is not
754 * <code>MODE_EXPLICIT</code>.
755 * @exception IllegalStateException if the tiling parameters have
756 * not been set.
757 *
758 * @see #setTiling(int, int, int, int)
759 * @see #getTileGridXOffset()
760 */
761 public int getTileGridYOffset() {
762 if (!canWriteTiles()) {
763 throw new UnsupportedOperationException("Tiling not supported!");
764 }
765 if (getTilingMode() != MODE_EXPLICIT) {
766 throw new IllegalStateException("Tiling mode not MODE_EXPLICIT!");
767 }
768 if (!tilingSet) {
769 throw new IllegalStateException("Tiling parameters not set!");
770 }
771 return tileGridYOffset;
772 }
773
774 /**
775 * Returns <code>true</code> if the writer can write out images
776 * as a series of passes of progressively increasing quality.
777 *
778 * @return <code>true</code> if the writer supports progressive
779 * encoding.
780 *
781 * @see #setProgressiveMode
782 * @see #getProgressiveMode
783 */
784 public boolean canWriteProgressive() {
785 return canWriteProgressive;
786 }
787
788 /**
789 * Specifies that the writer is to write the image out in a
790 * progressive mode such that the stream will contain a series of
791 * scans of increasing quality. If progressive encoding is not
792 * supported, an <code>UnsupportedOperationException</code> will
793 * be thrown.
794 *
795 * <p> The mode argument determines how
796 * the progression parameters are chosen, and must be either
797 * <code>MODE_DISABLED</code>,
798 * <code>MODE_COPY_FROM_METADATA</code>, or
799 * <code>MODE_DEFAULT</code>. Otherwise an
800 * <code>IllegalArgumentException</code> is thrown.
801 *
802 * <p> The modes are interpreted as follows:
803 *
804 * <ul>
805 * <li><code>MODE_DISABLED</code> - No progression. Use this to
806 * turn off progression.
807 *
808 * <li><code>MODE_COPY_FROM_METADATA</code> - The output image
809 * will use whatever progression parameters are found in the
810 * metadata objects passed into the writer.
811 *
812 * <li><code>MODE_DEFAULT</code> - The image will be written
813 * progressively, with parameters chosen by the writer.
814 * </ul>
815 *
816 * <p> The default is <code>MODE_COPY_FROM_METADATA</code>.
817 *
818 * @param mode The mode for setting progression in the output
819 * stream.
820 *
821 * @exception UnsupportedOperationException if the writer does not
822 * support progressive encoding.
823 * @exception IllegalArgumentException if <code>mode</code> is not
824 * one of the modes listed above.
825 *
826 * @see #getProgressiveMode
827 */
828 public void setProgressiveMode(int mode) {
829 if (!canWriteProgressive()) {
830 throw new UnsupportedOperationException(
831 "Progressive output not supported");
832 }
833 if (mode < MODE_DISABLED || mode > MAX_MODE) {
834 throw new IllegalArgumentException("Illegal value for mode!");
835 }
836 if (mode == MODE_EXPLICIT) {
837 throw new IllegalArgumentException(
838 "MODE_EXPLICIT not supported for progressive output");
839 }
840 this.progressiveMode = mode;
841 }
842
843 /**
844 * Returns the current mode for writing the stream in a
845 * progressive manner.
846 *
847 * @return the current mode for progressive encoding.
848 *
849 * @exception UnsupportedOperationException if the writer does not
850 * support progressive encoding.
851 *
852 * @see #setProgressiveMode
853 */
854 public int getProgressiveMode() {
855 if (!canWriteProgressive()) {
856 throw new UnsupportedOperationException
857 ("Progressive output not supported");
858 }
859 return progressiveMode;
860 }
861
862 /**
863 * Returns <code>true</code> if this writer supports compression.
864 *
865 * @return <code>true</code> if the writer supports compression.
866 */
867 public boolean canWriteCompressed() {
868 return canWriteCompressed;
869 }
870
871 /**
872 * Specifies whether compression is to be performed, and if so how
873 * compression parameters are to be determined. The <code>mode</code>
874 * argument must be one of the four modes, interpreted as follows:
875 *
876 * <ul>
877 * <li><code>MODE_DISABLED</code> - If the mode is set to
878 * <code>MODE_DISABLED</code>, methods that query or modify the
879 * compression type or parameters will throw an
880 * <code>IllegalStateException</code> (if compression is
881 * normally supported by the plug-in). Some writers, such as JPEG,
882 * do not normally offer uncompressed output. In this case, attempting
883 * to set the mode to <code>MODE_DISABLED</code> will throw an
884 * <code>UnsupportedOperationException</code> and the mode will not be
885 * changed.
886 *
887 * <li><code>MODE_EXPLICIT</code> - Compress using the
888 * compression type and quality settings specified in this
889 * <code>ImageWriteParam</code>. Any previously set compression
890 * parameters are discarded.
891 *
892 * <li><code>MODE_COPY_FROM_METADATA</code> - Use whatever
893 * compression parameters are specified in metadata objects
894 * passed in to the writer.
895 *
896 * <li><code>MODE_DEFAULT</code> - Use default compression
897 * parameters.
898 * </ul>
899 *
900 * <p> The default is <code>MODE_COPY_FROM_METADATA</code>.
901 *
902 * @param mode The mode for setting compression in the output
903 * stream.
904 *
905 * @exception UnsupportedOperationException if the writer does not
906 * support compression, or does not support the requested mode.
907 * @exception IllegalArgumentException if <code>mode</code> is not
908 * one of the modes listed above.
909 *
910 * @see #getCompressionMode
911 */
912 public void setCompressionMode(int mode) {
913 if (!canWriteCompressed()) {
914 throw new UnsupportedOperationException(
915 "Compression not supported.");
916 }
917 if (mode < MODE_DISABLED || mode > MAX_MODE) {
918 throw new IllegalArgumentException("Illegal value for mode!");
919 }
920 this.compressionMode = mode;
921 if (mode == MODE_EXPLICIT) {
922 unsetCompression();
923 }
924 }
925
926 /**
927 * Returns the current compression mode, if compression is
928 * supported.
929 *
930 * @return the current compression mode.
931 *
932 * @exception UnsupportedOperationException if the writer does not
933 * support compression.
934 *
935 * @see #setCompressionMode
936 */
937 public int getCompressionMode() {
938 if (!canWriteCompressed()) {
939 throw new UnsupportedOperationException(
940 "Compression not supported.");
941 }
942 return compressionMode;
943 }
944
945 /**
946 * Returns a list of available compression types, as an array or
947 * <code>String</code>s, or <code>null</code> if a compression
948 * type may not be chosen using these interfaces. The array
949 * returned is a copy.
950 *
951 * <p> If the writer only offers a single, mandatory form of
952 * compression, it is not necessary to provide any named
953 * compression types. Named compression types should only be
954 * used where the user is able to make a meaningful choice
955 * between different schemes.
956 *
957 * <p> The default implementation checks if compression is
958 * supported and throws an
959 * <code>UnsupportedOperationException</code> if not. Otherwise,
960 * it returns a clone of the <code>compressionTypes</code>
961 * instance variable if it is non-<code>null</code>, or else
962 * returns <code>null</code>.
963 *
964 * @return an array of <code>String</code>s containing the
965 * (non-localized) names of available compression types, or
966 * <code>null</code>.
967 *
968 * @exception UnsupportedOperationException if the writer does not
969 * support compression.
970 */
971 public String[] getCompressionTypes() {
972 if (!canWriteCompressed()) {
973 throw new UnsupportedOperationException(
974 "Compression not supported");
975 }
976 if (compressionTypes == null) {
977 return null;
978 }
979 return compressionTypes.clone();
980 }
981
982 /**
983 * Sets the compression type to one of the values indicated by
984 * <code>getCompressionTypes</code>. If a value of
985 * <code>null</code> is passed in, any previous setting is
986 * removed.
987 *
988 * <p> The default implementation checks whether compression is
989 * supported and the compression mode is
990 * <code>MODE_EXPLICIT</code>. If so, it calls
991 * <code>getCompressionTypes</code> and checks if
992 * <code>compressionType</code> is one of the legal values. If it
993 * is, the <code>compressionType</code> instance variable is set.
994 * If <code>compressionType</code> is <code>null</code>, the
995 * instance variable is set without performing any checking.
996 *
997 * @param compressionType one of the <code>String</code>s returned
998 * by <code>getCompressionTypes</code>, or <code>null</code> to
999 * remove any previous setting.
1000 *
1001 * @exception UnsupportedOperationException if the writer does not
1002 * support compression.
1003 * @exception IllegalStateException if the compression mode is not
1004 * <code>MODE_EXPLICIT</code>.
1005 * @exception UnsupportedOperationException if there are no
1006 * settable compression types.
1007 * @exception IllegalArgumentException if
1008 * <code>compressionType</code> is non-<code>null</code> but is not
1009 * one of the values returned by <code>getCompressionTypes</code>.
1010 *
1011 * @see #getCompressionTypes
1012 * @see #getCompressionType
1013 * @see #unsetCompression
1014 */
1015 public void setCompressionType(String compressionType) {
1016 if (!canWriteCompressed()) {
1017 throw new UnsupportedOperationException(
1018 "Compression not supported");
1019 }
1020 if (getCompressionMode() != MODE_EXPLICIT) {
1021 throw new IllegalStateException
1022 ("Compression mode not MODE_EXPLICIT!");
1023 }
1024 String[] legalTypes = getCompressionTypes();
1025 if (legalTypes == null) {
1026 throw new UnsupportedOperationException(
1027 "No settable compression types");
1028 }
1029 if (compressionType != null) {
1030 boolean found = false;
1031 if (legalTypes != null) {
1032 for (int i = 0; i < legalTypes.length; i++) {
1033 if (compressionType.equals(legalTypes[i])) {
1034 found = true;
1035 break;
1036 }
1037 }
1038 }
1039 if (!found) {
1040 throw new IllegalArgumentException("Unknown compression type!");
1041 }
1042 }
1043 this.compressionType = compressionType;
1044 }
1045
1046 /**
1047 * Returns the currently set compression type, or
1048 * <code>null</code> if none has been set. The type is returned
1049 * as a <code>String</code> from among those returned by
1050 * <code>getCompressionTypes</code>.
1051 * If no compression type has been set, <code>null</code> is
1052 * returned.
1053 *
1054 * <p> The default implementation checks whether compression is
1055 * supported and the compression mode is
1056 * <code>MODE_EXPLICIT</code>. If so, it returns the value of the
1057 * <code>compressionType</code> instance variable.
1058 *
1059 * @return the current compression type as a <code>String</code>,
1060 * or <code>null</code> if no type is set.
1061 *
1062 * @exception UnsupportedOperationException if the writer does not
1063 * support compression.
1064 * @exception IllegalStateException if the compression mode is not
1065 * <code>MODE_EXPLICIT</code>.
1066 *
1067 * @see #setCompressionType
1068 */
1069 public String getCompressionType() {
1070 if (!canWriteCompressed()) {
1071 throw new UnsupportedOperationException(
1072 "Compression not supported.");
1073 }
1074 if (getCompressionMode() != MODE_EXPLICIT) {
1075 throw new IllegalStateException
1076 ("Compression mode not MODE_EXPLICIT!");
1077 }
1078 return compressionType;
1079 }
1080
1081 /**
1082 * Removes any previous compression type and quality settings.
1083 *
1084 * <p> The default implementation sets the instance variable
1085 * <code>compressionType</code> to <code>null</code>, and the
1086 * instance variable <code>compressionQuality</code> to
1087 * <code>1.0F</code>.
1088 *
1089 * @exception UnsupportedOperationException if the plug-in does not
1090 * support compression.
1091 * @exception IllegalStateException if the compression mode is not
1092 * <code>MODE_EXPLICIT</code>.
1093 *
1094 * @see #setCompressionType
1095 * @see #setCompressionQuality
1096 */
1097 public void unsetCompression() {
1098 if (!canWriteCompressed()) {
1099 throw new UnsupportedOperationException(
1100 "Compression not supported");
1101 }
1102 if (getCompressionMode() != MODE_EXPLICIT) {
1103 throw new IllegalStateException
1104 ("Compression mode not MODE_EXPLICIT!");
1105 }
1106 this.compressionType = null;
1107 this.compressionQuality = 1.0F;
1108 }
1109
1110 /**
1111 * Returns a localized version of the name of the current
1112 * compression type, using the <code>Locale</code> returned by
1113 * <code>getLocale</code>.
1114 *
1115 * <p> The default implementation checks whether compression is
1116 * supported and the compression mode is
1117 * <code>MODE_EXPLICIT</code>. If so, if
1118 * <code>compressionType</code> is <code>non-null</code> the value
1119 * of <code>getCompressionType</code> is returned as a
1120 * convenience.
1121 *
1122 * @return a <code>String</code> containing a localized version of
1123 * the name of the current compression type.
1124 *
1125 * @exception UnsupportedOperationException if the writer does not
1126 * support compression.
1127 * @exception IllegalStateException if the compression mode is not
1128 * <code>MODE_EXPLICIT</code>.
1129 * @exception IllegalStateException if no compression type is set.
1130 */
1131 public String getLocalizedCompressionTypeName() {
1132 if (!canWriteCompressed()) {
1133 throw new UnsupportedOperationException(
1134 "Compression not supported.");
1135 }
1136 if (getCompressionMode() != MODE_EXPLICIT) {
1137 throw new IllegalStateException
1138 ("Compression mode not MODE_EXPLICIT!");
1139 }
1140 if (getCompressionType() == null) {
1141 throw new IllegalStateException("No compression type set!");
1142 }
1143 return getCompressionType();
1144 }
1145
1146 /**
1147 * Returns <code>true</code> if the current compression type
1148 * provides lossless compression. If a plug-in provides only
1149 * one mandatory compression type, then this method may be
1150 * called without calling <code>setCompressionType</code> first.
1151 *
1152 * <p> If there are multiple compression types but none has
1153 * been set, an <code>IllegalStateException</code> is thrown.
1154 *
1155 * <p> The default implementation checks whether compression is
1156 * supported and the compression mode is
1157 * <code>MODE_EXPLICIT</code>. If so, if
1158 * <code>getCompressionTypes()</code> is <code>null</code> or
1159 * <code>getCompressionType()</code> is non-<code>null</code>
1160 * <code>true</code> is returned as a convenience.
1161 *
1162 * @return <code>true</code> if the current compression type is
1163 * lossless.
1164 *
1165 * @exception UnsupportedOperationException if the writer does not
1166 * support compression.
1167 * @exception IllegalStateException if the compression mode is not
1168 * <code>MODE_EXPLICIT</code>.
1169 * @exception IllegalStateException if the set of legal
1170 * compression types is non-<code>null</code> and the current
1171 * compression type is <code>null</code>.
1172 */
1173 public boolean isCompressionLossless() {
1174 if (!canWriteCompressed()) {
1175 throw new UnsupportedOperationException(
1176 "Compression not supported");
1177 }
1178 if (getCompressionMode() != MODE_EXPLICIT) {
1179 throw new IllegalStateException
1180 ("Compression mode not MODE_EXPLICIT!");
1181 }
1182 if ((getCompressionTypes() != null) &&
1183 (getCompressionType() == null)) {
1184 throw new IllegalStateException("No compression type set!");
1185 }
1186 return true;
1187 }
1188
1189 /**
1190 * Sets the compression quality to a value between <code>0</code>
1191 * and <code>1</code>. Only a single compression quality setting
1192 * is supported by default; writers can provide extended versions
1193 * of <code>ImageWriteParam</code> that offer more control. For
1194 * lossy compression schemes, the compression quality should
1195 * control the tradeoff between file size and image quality (for
1196 * example, by choosing quantization tables when writing JPEG
1197 * images). For lossless schemes, the compression quality may be
1198 * used to control the tradeoff between file size and time taken
1199 * to perform the compression (for example, by optimizing row
1200 * filters and setting the ZLIB compression level when writing
1201 * PNG images).
1202 *
1203 * <p> A compression quality setting of 0.0 is most generically
1204 * interpreted as "high compression is important," while a setting of
1205 * 1.0 is most generically interpreted as "high image quality is
1206 * important."
1207 *
1208 * <p> If there are multiple compression types but none has been
1209 * set, an <code>IllegalStateException</code> is thrown.
1210 *
1211 * <p> The default implementation checks that compression is
1212 * supported, and that the compression mode is
1213 * <code>MODE_EXPLICIT</code>. If so, if
1214 * <code>getCompressionTypes()</code> returns <code>null</code> or
1215 * <code>compressionType</code> is non-<code>null</code> it sets
1216 * the <code>compressionQuality</code> instance variable.
1217 *
1218 * @param quality a <code>float</code> between <code>0</code>and
1219 * <code>1</code> indicating the desired quality level.
1220 *
1221 * @exception UnsupportedOperationException if the writer does not
1222 * support compression.
1223 * @exception IllegalStateException if the compression mode is not
1224 * <code>MODE_EXPLICIT</code>.
1225 * @exception IllegalStateException if the set of legal
1226 * compression types is non-<code>null</code> and the current
1227 * compression type is <code>null</code>.
1228 * @exception IllegalArgumentException if <code>quality</code> is
1229 * not between <code>0</code>and <code>1</code>, inclusive.
1230 *
1231 * @see #getCompressionQuality
1232 */
1233 public void setCompressionQuality(float quality) {
1234 if (!canWriteCompressed()) {
1235 throw new UnsupportedOperationException(
1236 "Compression not supported");
1237 }
1238 if (getCompressionMode() != MODE_EXPLICIT) {
1239 throw new IllegalStateException
1240 ("Compression mode not MODE_EXPLICIT!");
1241 }
1242 if (getCompressionTypes() != null && getCompressionType() == null) {
1243 throw new IllegalStateException("No compression type set!");
1244 }
1245 if (quality < 0.0F || quality > 1.0F) {
1246 throw new IllegalArgumentException("Quality out-of-bounds!");
1247 }
1248 this.compressionQuality = quality;
1249 }
1250
1251 /**
1252 * Returns the current compression quality setting.
1253 *
1254 * <p> If there are multiple compression types but none has been
1255 * set, an <code>IllegalStateException</code> is thrown.
1256 *
1257 * <p> The default implementation checks that compression is
1258 * supported and that the compression mode is
1259 * <code>MODE_EXPLICIT</code>. If so, if
1260 * <code>getCompressionTypes()</code> is <code>null</code> or
1261 * <code>getCompressionType()</code> is non-<code>null</code>, it
1262 * returns the value of the <code>compressionQuality</code>
1263 * instance variable.
1264 *
1265 * @return the current compression quality setting.
1266 *
1267 * @exception UnsupportedOperationException if the writer does not
1268 * support compression.
1269 * @exception IllegalStateException if the compression mode is not
1270 * <code>MODE_EXPLICIT</code>.
1271 * @exception IllegalStateException if the set of legal
1272 * compression types is non-<code>null</code> and the current
1273 * compression type is <code>null</code>.
1274 *
1275 * @see #setCompressionQuality
1276 */
1277 public float getCompressionQuality() {
1278 if (!canWriteCompressed()) {
1279 throw new UnsupportedOperationException(
1280 "Compression not supported.");
1281 }
1282 if (getCompressionMode() != MODE_EXPLICIT) {
1283 throw new IllegalStateException
1284 ("Compression mode not MODE_EXPLICIT!");
1285 }
1286 if ((getCompressionTypes() != null) &&
1287 (getCompressionType() == null)) {
1288 throw new IllegalStateException("No compression type set!");
1289 }
1290 return compressionQuality;
1291 }
1292
1293
1294 /**
1295 * Returns a <code>float</code> indicating an estimate of the
1296 * number of bits of output data for each bit of input image data
1297 * at the given quality level. The value will typically lie
1298 * between <code>0</code> and <code>1</code>, with smaller values
1299 * indicating more compression. A special value of
1300 * <code>-1.0F</code> is used to indicate that no estimate is
1301 * available.
1302 *
1303 * <p> If there are multiple compression types but none has been set,
1304 * an <code>IllegalStateException</code> is thrown.
1305 *
1306 * <p> The default implementation checks that compression is
1307 * supported and the compression mode is
1308 * <code>MODE_EXPLICIT</code>. If so, if
1309 * <code>getCompressionTypes()</code> is <code>null</code> or
1310 * <code>getCompressionType()</code> is non-<code>null</code>, and
1311 * <code>quality</code> is within bounds, it returns
1312 * <code>-1.0</code>.
1313 *
1314 * @param quality the quality setting whose bit rate is to be
1315 * queried.
1316 *
1317 * @return an estimate of the compressed bit rate, or
1318 * <code>-1.0F</code> if no estimate is available.
1319 *
1320 * @exception UnsupportedOperationException if the writer does not
1321 * support compression.
1322 * @exception IllegalStateException if the compression mode is not
1323 * <code>MODE_EXPLICIT</code>.
1324 * @exception IllegalStateException if the set of legal
1325 * compression types is non-<code>null</code> and the current
1326 * compression type is <code>null</code>.
1327 * @exception IllegalArgumentException if <code>quality</code> is
1328 * not between <code>0</code>and <code>1</code>, inclusive.
1329 */
1330 public float getBitRate(float quality) {
1331 if (!canWriteCompressed()) {
1332 throw new UnsupportedOperationException(
1333 "Compression not supported.");
1334 }
1335 if (getCompressionMode() != MODE_EXPLICIT) {
1336 throw new IllegalStateException
1337 ("Compression mode not MODE_EXPLICIT!");
1338 }
1339 if ((getCompressionTypes() != null) &&
1340 (getCompressionType() == null)) {
1341 throw new IllegalStateException("No compression type set!");
1342 }
1343 if (quality < 0.0F || quality > 1.0F) {
1344 throw new IllegalArgumentException("Quality out-of-bounds!");
1345 }
1346 return -1.0F;
1347 }
1348
1349 /**
1350 * Returns an array of <code>String</code>s that may be used along
1351 * with <code>getCompressionQualityValues</code> as part of a user
1352 * interface for setting or displaying the compression quality
1353 * level. The <code>String</code> with index <code>i</code>
1354 * provides a description of the range of quality levels between
1355 * <code>getCompressionQualityValues[i]</code> and
1356 * <code>getCompressionQualityValues[i + 1]</code>. Note that the
1357 * length of the array returned from
1358 * <code>getCompressionQualityValues</code> will always be one
1359 * greater than that returned from
1360 * <code>getCompressionQualityDescriptions</code>.
1361 *
1362 * <p> As an example, the strings "Good", "Better", and "Best"
1363 * could be associated with the ranges <code>[0, .33)</code>,
1364 * <code>[.33, .66)</code>, and <code>[.66, 1.0]</code>. In this
1365 * case, <code>getCompressionQualityDescriptions</code> would
1366 * return <code>{ "Good", "Better", "Best" }</code> and
1367 * <code>getCompressionQualityValues</code> would return
1368 * <code>{ 0.0F, .33F, .66F, 1.0F }</code>.
1369 *
1370 * <p> If no descriptions are available, <code>null</code> is
1371 * returned. If <code>null</code> is returned from
1372 * <code>getCompressionQualityValues</code>, this method must also
1373 * return <code>null</code>.
1374 *
1375 * <p> The descriptions should be localized for the
1376 * <code>Locale</code> returned by <code>getLocale</code>, if it
1377 * is non-<code>null</code>.
1378 *
1379 * <p> If there are multiple compression types but none has been set,
1380 * an <code>IllegalStateException</code> is thrown.
1381 *
1382 * <p> The default implementation checks that compression is
1383 * supported and that the compression mode is
1384 * <code>MODE_EXPLICIT</code>. If so, if
1385 * <code>getCompressionTypes()</code> is <code>null</code> or
1386 * <code>getCompressionType()</code> is non-<code>null</code>, it
1387 * returns <code>null</code>.
1388 *
1389 * @return an array of <code>String</code>s containing localized
1390 * descriptions of the compression quality levels.
1391 *
1392 * @exception UnsupportedOperationException if the writer does not
1393 * support compression.
1394 * @exception IllegalStateException if the compression mode is not
1395 * <code>MODE_EXPLICIT</code>.
1396 * @exception IllegalStateException if the set of legal
1397 * compression types is non-<code>null</code> and the current
1398 * compression type is <code>null</code>.
1399 *
1400 * @see #getCompressionQualityValues
1401 */
1402 public String[] getCompressionQualityDescriptions() {
1403 if (!canWriteCompressed()) {
1404 throw new UnsupportedOperationException(
1405 "Compression not supported.");
1406 }
1407 if (getCompressionMode() != MODE_EXPLICIT) {
1408 throw new IllegalStateException
1409 ("Compression mode not MODE_EXPLICIT!");
1410 }
1411 if ((getCompressionTypes() != null) &&
1412 (getCompressionType() == null)) {
1413 throw new IllegalStateException("No compression type set!");
1414 }
1415 return null;
1416 }
1417
1418 /**
1419 * Returns an array of <code>float</code>s that may be used along
1420 * with <code>getCompressionQualityDescriptions</code> as part of a user
1421 * interface for setting or displaying the compression quality
1422 * level. See {@link #getCompressionQualityDescriptions
1423 * getCompressionQualityDescriptions} for more information.
1424 *
1425 * <p> If no descriptions are available, <code>null</code> is
1426 * returned. If <code>null</code> is returned from
1427 * <code>getCompressionQualityDescriptions</code>, this method
1428 * must also return <code>null</code>.
1429 *
1430 * <p> If there are multiple compression types but none has been set,
1431 * an <code>IllegalStateException</code> is thrown.
1432 *
1433 * <p> The default implementation checks that compression is
1434 * supported and that the compression mode is
1435 * <code>MODE_EXPLICIT</code>. If so, if
1436 * <code>getCompressionTypes()</code> is <code>null</code> or
1437 * <code>getCompressionType()</code> is non-<code>null</code>, it
1438 * returns <code>null</code>.
1439 *
1440 * @return an array of <code>float</code>s indicating the
1441 * boundaries between the compression quality levels as described
1442 * by the <code>String</code>s from
1443 * <code>getCompressionQualityDescriptions</code>.
1444 *
1445 * @exception UnsupportedOperationException if the writer does not
1446 * support compression.
1447 * @exception IllegalStateException if the compression mode is not
1448 * <code>MODE_EXPLICIT</code>.
1449 * @exception IllegalStateException if the set of legal
1450 * compression types is non-<code>null</code> and the current
1451 * compression type is <code>null</code>.
1452 *
1453 * @see #getCompressionQualityDescriptions
1454 */
1455 public float[] getCompressionQualityValues() {
1456 if (!canWriteCompressed()) {
1457 throw new UnsupportedOperationException(
1458 "Compression not supported.");
1459 }
1460 if (getCompressionMode() != MODE_EXPLICIT) {
1461 throw new IllegalStateException
1462 ("Compression mode not MODE_EXPLICIT!");
1463 }
1464 if ((getCompressionTypes() != null) &&
1465 (getCompressionType() == null)) {
1466 throw new IllegalStateException("No compression type set!");
1467 }
1468 return null;
1469 }
1470 }