J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2001 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; |
| 27 | |
| 28 | import java.awt.Point; |
| 29 | import java.awt.Rectangle; |
| 30 | |
| 31 | /** |
| 32 | * A superclass of all classes describing how streams should be |
| 33 | * decoded or encoded. This class contains all the variables and |
| 34 | * methods that are shared by <code>ImageReadParam</code> and |
| 35 | * <code>ImageWriteParam</code>. |
| 36 | * |
| 37 | * <p> This class provides mechanisms to specify a source region and a |
| 38 | * destination region. When reading, the source is the stream and |
| 39 | * the in-memory image is the destination. When writing, these are |
| 40 | * reversed. In the case of writing, destination regions may be used |
| 41 | * only with a writer that supports pixel replacement. |
| 42 | * <p> |
| 43 | * Decimation subsampling may be specified for both readers |
| 44 | * and writers, using a movable subsampling grid. |
| 45 | * <p> |
| 46 | * Subsets of the source and destination bands may be selected. |
| 47 | * |
| 48 | */ |
| 49 | public abstract class IIOParam { |
| 50 | |
| 51 | /** |
| 52 | * The source region, on <code>null</code> if none is set. |
| 53 | */ |
| 54 | protected Rectangle sourceRegion = null; |
| 55 | |
| 56 | /** |
| 57 | * The decimation subsampling to be applied in the horizontal |
| 58 | * direction. By default, the value is <code>1</code>. |
| 59 | * The value must not be negative or 0. |
| 60 | */ |
| 61 | protected int sourceXSubsampling = 1; |
| 62 | |
| 63 | /** |
| 64 | * The decimation subsampling to be applied in the vertical |
| 65 | * direction. By default, the value is <code>1</code>. |
| 66 | * The value must not be negative or 0. |
| 67 | */ |
| 68 | protected int sourceYSubsampling = 1; |
| 69 | |
| 70 | /** |
| 71 | * A horizontal offset to be applied to the subsampling grid before |
| 72 | * subsampling. The first pixel to be used will be offset this |
| 73 | * amount from the origin of the region, or of the image if no |
| 74 | * region is specified. |
| 75 | */ |
| 76 | protected int subsamplingXOffset = 0; |
| 77 | |
| 78 | /** |
| 79 | * A vertical offset to be applied to the subsampling grid before |
| 80 | * subsampling. The first pixel to be used will be offset this |
| 81 | * amount from the origin of the region, or of the image if no |
| 82 | * region is specified. |
| 83 | */ |
| 84 | protected int subsamplingYOffset = 0; |
| 85 | |
| 86 | /** |
| 87 | * An array of <code>int</code>s indicating which source bands |
| 88 | * will be used, or <code>null</code>. If <code>null</code>, the |
| 89 | * set of source bands to be used is as described in the comment |
| 90 | * for the <code>setSourceBands</code> method. No value should |
| 91 | * be allowed to be negative. |
| 92 | */ |
| 93 | protected int[] sourceBands = null; |
| 94 | |
| 95 | /** |
| 96 | * An <code>ImageTypeSpecifier</code> to be used to generate a |
| 97 | * destination image when reading, or to set the output color type |
| 98 | * when writing. If non has been setm the value will be |
| 99 | * <code>null</code>. By default, the value is <code>null</code>. |
| 100 | */ |
| 101 | protected ImageTypeSpecifier destinationType = null; |
| 102 | |
| 103 | /** |
| 104 | * The offset in the destination where the upper-left decoded |
| 105 | * pixel should be placed. By default, the value is (0, 0). |
| 106 | */ |
| 107 | protected Point destinationOffset = new Point(0, 0); |
| 108 | |
| 109 | /** |
| 110 | * The default <code>IIOParamController</code> that will be |
| 111 | * used to provide settings for this <code>IIOParam</code> |
| 112 | * object when the <code>activateController</code> method |
| 113 | * is called. This default should be set by subclasses |
| 114 | * that choose to provide their own default controller, |
| 115 | * usually a GUI, for setting parameters. |
| 116 | * |
| 117 | * @see IIOParamController |
| 118 | * @see #getDefaultController |
| 119 | * @see #activateController |
| 120 | */ |
| 121 | protected IIOParamController defaultController = null; |
| 122 | |
| 123 | /** |
| 124 | * The <code>IIOParamController</code> that will be |
| 125 | * used to provide settings for this <code>IIOParam</code> |
| 126 | * object when the <code>activateController</code> method |
| 127 | * is called. This value overrides any default controller, |
| 128 | * even when null. |
| 129 | * |
| 130 | * @see IIOParamController |
| 131 | * @see #setController(IIOParamController) |
| 132 | * @see #hasController() |
| 133 | * @see #activateController() |
| 134 | */ |
| 135 | protected IIOParamController controller = null; |
| 136 | |
| 137 | /** |
| 138 | * Protected constructor may be called only by subclasses. |
| 139 | */ |
| 140 | protected IIOParam() { |
| 141 | controller = defaultController; |
| 142 | } |
| 143 | |
| 144 | /** |
| 145 | * Sets the source region of interest. The region of interest is |
| 146 | * described as a rectangle, with the upper-left corner of the |
| 147 | * source image as pixel (0, 0) and increasing values down and to |
| 148 | * the right. The actual number of pixels used will depend on |
| 149 | * the subsampling factors set by <code>setSourceSubsampling</code>. |
| 150 | * If subsampling has been set such that this number is zero, |
| 151 | * an <code>IllegalStateException</code> will be thrown. |
| 152 | * |
| 153 | * <p> The source region of interest specified by this method will |
| 154 | * be clipped as needed to fit within the source bounds, as well |
| 155 | * as the destination offsets, width, and height at the time of |
| 156 | * actual I/O. |
| 157 | * |
| 158 | * <p> A value of <code>null</code> for <code>sourceRegion</code> |
| 159 | * will remove any region specification, causing the entire image |
| 160 | * to be used. |
| 161 | * |
| 162 | * @param sourceRegion a <code>Rectangle</code> specifying the |
| 163 | * source region of interest, or <code>null</code>. |
| 164 | * |
| 165 | * @exception IllegalArgumentException if |
| 166 | * <code>sourceRegion</code> is non-<code>null</code> and either |
| 167 | * <code>sourceRegion.x</code> or <code>sourceRegion.y</code> is |
| 168 | * negative. |
| 169 | * @exception IllegalArgumentException if |
| 170 | * <code>sourceRegion</code> is non-<code>null</code> and either |
| 171 | * <code>sourceRegion.width</code> or |
| 172 | * <code>sourceRegion.height</code> is negative or 0. |
| 173 | * @exception IllegalStateException if subsampling is such that |
| 174 | * this region will have a subsampled width or height of zero. |
| 175 | * |
| 176 | * @see #getSourceRegion |
| 177 | * @see #setSourceSubsampling |
| 178 | * @see ImageReadParam#setDestinationOffset |
| 179 | * @see ImageReadParam#getDestinationOffset |
| 180 | */ |
| 181 | public void setSourceRegion(Rectangle sourceRegion) { |
| 182 | if (sourceRegion == null) { |
| 183 | this.sourceRegion = null; |
| 184 | return; |
| 185 | } |
| 186 | |
| 187 | if (sourceRegion.x < 0) { |
| 188 | throw new IllegalArgumentException("sourceRegion.x < 0!"); |
| 189 | } |
| 190 | if (sourceRegion.y < 0){ |
| 191 | throw new IllegalArgumentException("sourceRegion.y < 0!"); |
| 192 | } |
| 193 | if (sourceRegion.width <= 0) { |
| 194 | throw new IllegalArgumentException("sourceRegion.width <= 0!"); |
| 195 | } |
| 196 | if (sourceRegion.height <= 0) { |
| 197 | throw new IllegalArgumentException("sourceRegion.height <= 0!"); |
| 198 | } |
| 199 | |
| 200 | // Throw an IllegalStateException if region falls between subsamples |
| 201 | if (sourceRegion.width <= subsamplingXOffset) { |
| 202 | throw new IllegalStateException |
| 203 | ("sourceRegion.width <= subsamplingXOffset!"); |
| 204 | } |
| 205 | if (sourceRegion.height <= subsamplingYOffset) { |
| 206 | throw new IllegalStateException |
| 207 | ("sourceRegion.height <= subsamplingYOffset!"); |
| 208 | } |
| 209 | |
| 210 | this.sourceRegion = (Rectangle)sourceRegion.clone(); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Returns the source region to be used. The returned value is |
| 215 | * that set by the most recent call to |
| 216 | * <code>setSourceRegion</code>, and will be <code>null</code> if |
| 217 | * there is no region set. |
| 218 | * |
| 219 | * @return the source region of interest as a |
| 220 | * <code>Rectangle</code>, or <code>null</code>. |
| 221 | * |
| 222 | * @see #setSourceRegion |
| 223 | */ |
| 224 | public Rectangle getSourceRegion() { |
| 225 | if (sourceRegion == null) { |
| 226 | return null; |
| 227 | } |
| 228 | return (Rectangle)sourceRegion.clone(); |
| 229 | } |
| 230 | |
| 231 | /** |
| 232 | * Specifies a decimation subsampling to apply on I/O. The |
| 233 | * <code>sourceXSubsampling</code> and |
| 234 | * <code>sourceYSubsampling</code> parameters specify the |
| 235 | * subsampling period (<i>i.e.</i>, the number of rows and columns |
| 236 | * to advance after every source pixel). Specifically, a period of |
| 237 | * 1 will use every row or column; a period of 2 will use every |
| 238 | * other row or column. The <code>subsamplingXOffset</code> and |
| 239 | * <code>subsamplingYOffset</code> parameters specify an offset |
| 240 | * from the region (or image) origin for the first subsampled pixel. |
| 241 | * Adjusting the origin of the subsample grid is useful for avoiding |
| 242 | * seams when subsampling a very large source image into destination |
| 243 | * regions that will be assembled into a complete subsampled image. |
| 244 | * Most users will want to simply leave these parameters at 0. |
| 245 | * |
| 246 | * <p> The number of pixels and scanlines to be used are calculated |
| 247 | * as follows. |
| 248 | * <p> |
| 249 | * The number of subsampled pixels in a scanline is given by |
| 250 | * <p> |
| 251 | * <code>truncate[(width - subsamplingXOffset + sourceXSubsampling - 1) |
| 252 | * / sourceXSubsampling]</code>. |
| 253 | * <p> |
| 254 | * If the region is such that this width is zero, an |
| 255 | * <code>IllegalStateException</code> is thrown. |
| 256 | * <p> |
| 257 | * The number of scanlines to be used can be computed similarly. |
| 258 | * |
| 259 | * <p>The ability to set the subsampling grid to start somewhere |
| 260 | * other than the source region origin is useful if the |
| 261 | * region is being used to create subsampled tiles of a large image, |
| 262 | * where the tile width and height are not multiples of the |
| 263 | * subsampling periods. If the subsampling grid does not remain |
| 264 | * consistent from tile to tile, there will be artifacts at the tile |
| 265 | * boundaries. By adjusting the subsampling grid offset for each |
| 266 | * tile to compensate, these artifacts can be avoided. The tradeoff |
| 267 | * is that in order to avoid these artifacts, the tiles are not all |
| 268 | * the same size. The grid offset to use in this case is given by: |
| 269 | * <br> |
| 270 | * grid offset = [period - (region offset modulo period)] modulo period) |
| 271 | * |
| 272 | * <p> If either <code>sourceXSubsampling</code> or |
| 273 | * <code>sourceYSubsampling</code> is 0 or negative, an |
| 274 | * <code>IllegalArgumentException</code> will be thrown. |
| 275 | * |
| 276 | * <p> If either <code>subsamplingXOffset</code> or |
| 277 | * <code>subsamplingYOffset</code> is negative or greater than or |
| 278 | * equal to the corresponding period, an |
| 279 | * <code>IllegalArgumentException</code> will be thrown. |
| 280 | * |
| 281 | * <p> There is no <code>unsetSourceSubsampling</code> method; |
| 282 | * simply call <code>setSourceSubsampling(1, 1, 0, 0)</code> to |
| 283 | * restore default values. |
| 284 | * |
| 285 | * @param sourceXSubsampling the number of columns to advance |
| 286 | * between pixels. |
| 287 | * @param sourceYSubsampling the number of rows to advance between |
| 288 | * pixels. |
| 289 | * @param subsamplingXOffset the horizontal offset of the first subsample |
| 290 | * within the region, or within the image if no region is set. |
| 291 | * @param subsamplingYOffset the horizontal offset of the first subsample |
| 292 | * within the region, or within the image if no region is set. |
| 293 | * @exception IllegalArgumentException if either period is |
| 294 | * negative or 0, or if either grid offset is negative or greater than |
| 295 | * the corresponding period. |
| 296 | * @exception IllegalStateException if the source region is such that |
| 297 | * the subsampled output would contain no pixels. |
| 298 | */ |
| 299 | public void setSourceSubsampling(int sourceXSubsampling, |
| 300 | int sourceYSubsampling, |
| 301 | int subsamplingXOffset, |
| 302 | int subsamplingYOffset) { |
| 303 | if (sourceXSubsampling <= 0) { |
| 304 | throw new IllegalArgumentException("sourceXSubsampling <= 0!"); |
| 305 | } |
| 306 | if (sourceYSubsampling <= 0) { |
| 307 | throw new IllegalArgumentException("sourceYSubsampling <= 0!"); |
| 308 | } |
| 309 | if (subsamplingXOffset < 0 || |
| 310 | subsamplingXOffset >= sourceXSubsampling) { |
| 311 | throw new IllegalArgumentException |
| 312 | ("subsamplingXOffset out of range!"); |
| 313 | } |
| 314 | if (subsamplingYOffset < 0 || |
| 315 | subsamplingYOffset >= sourceYSubsampling) { |
| 316 | throw new IllegalArgumentException |
| 317 | ("subsamplingYOffset out of range!"); |
| 318 | } |
| 319 | |
| 320 | // Throw an IllegalStateException if region falls between subsamples |
| 321 | if (sourceRegion != null) { |
| 322 | if (subsamplingXOffset >= sourceRegion.width || |
| 323 | subsamplingYOffset >= sourceRegion.height) { |
| 324 | throw new IllegalStateException("region contains no pixels!"); |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | this.sourceXSubsampling = sourceXSubsampling; |
| 329 | this.sourceYSubsampling = sourceYSubsampling; |
| 330 | this.subsamplingXOffset = subsamplingXOffset; |
| 331 | this.subsamplingYOffset = subsamplingYOffset; |
| 332 | } |
| 333 | |
| 334 | /** |
| 335 | * Returns the number of source columns to advance for each pixel. |
| 336 | * |
| 337 | * <p>If <code>setSourceSubsampling</code> has not been called, 1 |
| 338 | * is returned (which is the correct value). |
| 339 | * |
| 340 | * @return the source subsampling X period. |
| 341 | * |
| 342 | * @see #setSourceSubsampling |
| 343 | * @see #getSourceYSubsampling |
| 344 | */ |
| 345 | public int getSourceXSubsampling() { |
| 346 | return sourceXSubsampling; |
| 347 | } |
| 348 | |
| 349 | /** |
| 350 | * Returns the number of rows to advance for each pixel. |
| 351 | * |
| 352 | * <p>If <code>setSourceSubsampling</code> has not been called, 1 |
| 353 | * is returned (which is the correct value). |
| 354 | * |
| 355 | * @return the source subsampling Y period. |
| 356 | * |
| 357 | * @see #setSourceSubsampling |
| 358 | * @see #getSourceXSubsampling |
| 359 | */ |
| 360 | public int getSourceYSubsampling() { |
| 361 | return sourceYSubsampling; |
| 362 | } |
| 363 | |
| 364 | /** |
| 365 | * Returns the horizontal offset of the subsampling grid. |
| 366 | * |
| 367 | * <p>If <code>setSourceSubsampling</code> has not been called, 0 |
| 368 | * is returned (which is the correct value). |
| 369 | * |
| 370 | * @return the source subsampling grid X offset. |
| 371 | * |
| 372 | * @see #setSourceSubsampling |
| 373 | * @see #getSubsamplingYOffset |
| 374 | */ |
| 375 | public int getSubsamplingXOffset() { |
| 376 | return subsamplingXOffset; |
| 377 | } |
| 378 | |
| 379 | /** |
| 380 | * Returns the vertical offset of the subsampling grid. |
| 381 | * |
| 382 | * <p>If <code>setSourceSubsampling</code> has not been called, 0 |
| 383 | * is returned (which is the correct value). |
| 384 | * |
| 385 | * @return the source subsampling grid Y offset. |
| 386 | * |
| 387 | * @see #setSourceSubsampling |
| 388 | * @see #getSubsamplingXOffset |
| 389 | */ |
| 390 | public int getSubsamplingYOffset() { |
| 391 | return subsamplingYOffset; |
| 392 | } |
| 393 | |
| 394 | /** |
| 395 | * Sets the indices of the source bands to be used. Duplicate |
| 396 | * indices are not allowed. |
| 397 | * |
| 398 | * <p> A <code>null</code> value indicates that all source bands |
| 399 | * will be used. |
| 400 | * |
| 401 | * <p> At the time of reading, an |
| 402 | * <code>IllegalArgumentException</code> will be thrown by the |
| 403 | * reader or writer if a value larger than the largest available |
| 404 | * source band index has been specified or if the number of source |
| 405 | * bands and destination bands to be used differ. The |
| 406 | * <code>ImageReader.checkReadParamBandSettings</code> method may |
| 407 | * be used to automate this test. |
| 408 | * |
| 409 | * <p> Semantically, a copy is made of the array; changes to the |
| 410 | * array contents subsequent to this call have no effect on |
| 411 | * this <code>IIOParam</code>. |
| 412 | * |
| 413 | * @param sourceBands an array of integer band indices to be |
| 414 | * used. |
| 415 | * |
| 416 | * @exception IllegalArgumentException if <code>sourceBands</code> |
| 417 | * contains a negative or duplicate value. |
| 418 | * |
| 419 | * @see #getSourceBands |
| 420 | * @see ImageReadParam#setDestinationBands |
| 421 | * @see ImageReader#checkReadParamBandSettings |
| 422 | */ |
| 423 | public void setSourceBands(int[] sourceBands) { |
| 424 | if (sourceBands == null) { |
| 425 | this.sourceBands = null; |
| 426 | } else { |
| 427 | int numBands = sourceBands.length; |
| 428 | for (int i = 0; i < numBands; i++) { |
| 429 | int band = sourceBands[i]; |
| 430 | if (band < 0) { |
| 431 | throw new IllegalArgumentException("Band value < 0!"); |
| 432 | } |
| 433 | for (int j = i + 1; j < numBands; j++) { |
| 434 | if (band == sourceBands[j]) { |
| 435 | throw new IllegalArgumentException("Duplicate band value!"); |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | } |
| 440 | this.sourceBands = (int[])(sourceBands.clone()); |
| 441 | } |
| 442 | } |
| 443 | |
| 444 | /** |
| 445 | * Returns the set of of source bands to be used. The returned |
| 446 | * value is that set by the most recent call to |
| 447 | * <code>setSourceBands</code>, or <code>null</code> if there have |
| 448 | * been no calls to <code>setSourceBands</code>. |
| 449 | * |
| 450 | * <p> Semantically, the array returned is a copy; changes to |
| 451 | * array contents subsequent to this call have no effect on this |
| 452 | * <code>IIOParam</code>. |
| 453 | * |
| 454 | * @return the set of source bands to be used, or |
| 455 | * <code>null</code>. |
| 456 | * |
| 457 | * @see #setSourceBands |
| 458 | */ |
| 459 | public int[] getSourceBands() { |
| 460 | if (sourceBands == null) { |
| 461 | return null; |
| 462 | } |
| 463 | return (int[])(sourceBands.clone()); |
| 464 | } |
| 465 | |
| 466 | /** |
| 467 | * Sets the desired image type for the destination image, using an |
| 468 | * <code>ImageTypeSpecifier</code>. |
| 469 | * |
| 470 | * <p> When reading, if the layout of the destination has been set |
| 471 | * using this method, each call to an <code>ImageReader</code> |
| 472 | * <code>read</code> method will return a new |
| 473 | * <code>BufferedImage</code> using the format specified by the |
| 474 | * supplied type specifier. As a side effect, any destination |
| 475 | * <code>BufferedImage</code> set by |
| 476 | * <code>ImageReadParam.setDestination(BufferedImage)</code> will |
| 477 | * no longer be set as the destination. In other words, this |
| 478 | * method may be thought of as calling |
| 479 | * <code>setDestination((BufferedImage)null)</code>. |
| 480 | * |
| 481 | * <p> When writing, the destination type maybe used to determine |
| 482 | * the color type of the image. The <code>SampleModel</code> |
| 483 | * information will be ignored, and may be <code>null</code>. For |
| 484 | * example, a 4-banded image could represent either CMYK or RGBA |
| 485 | * data. If a destination type is set, its |
| 486 | * <code>ColorModel</code> will override any |
| 487 | * <code>ColorModel</code> on the image itself. This is crucial |
| 488 | * when <code>setSourceBands</code> is used since the image's |
| 489 | * <code>ColorModel</code> will refer to the entire image rather |
| 490 | * than to the subset of bands being written. |
| 491 | * |
| 492 | * @param destinationType the <code>ImageTypeSpecifier</code> to |
| 493 | * be used to determine the destination layout and color type. |
| 494 | * |
| 495 | * @see #getDestinationType |
| 496 | */ |
| 497 | public void setDestinationType(ImageTypeSpecifier destinationType) { |
| 498 | this.destinationType = destinationType; |
| 499 | } |
| 500 | |
| 501 | /** |
| 502 | * Returns the type of image to be returned by the read, if one |
| 503 | * was set by a call to |
| 504 | * <code>setDestination(ImageTypeSpecifier)</code>, as an |
| 505 | * <code>ImageTypeSpecifier</code>. If none was set, |
| 506 | * <code>null</code> is returned. |
| 507 | * |
| 508 | * @return an <code>ImageTypeSpecifier</code> describing the |
| 509 | * destination type, or <code>null</code>. |
| 510 | * |
| 511 | * @see #setDestinationType |
| 512 | */ |
| 513 | public ImageTypeSpecifier getDestinationType() { |
| 514 | return destinationType; |
| 515 | } |
| 516 | |
| 517 | /** |
| 518 | * Specifies the offset in the destination image at which future |
| 519 | * decoded pixels are to be placed, when reading, or where a |
| 520 | * region will be written, when writing. |
| 521 | * |
| 522 | * <p> When reading, the region to be written within the |
| 523 | * destination <code>BufferedImage</code> will start at this |
| 524 | * offset and have a width and height determined by the source |
| 525 | * region of interest, the subsampling parameters, and the |
| 526 | * destination bounds. |
| 527 | * |
| 528 | * <p> Normal writes are not affected by this method, only writes |
| 529 | * performed using <code>ImageWriter.replacePixels</code>. For |
| 530 | * such writes, the offset specified is within the output stream |
| 531 | * image whose pixels are being modified. |
| 532 | * |
| 533 | * <p> There is no <code>unsetDestinationOffset</code> method; |
| 534 | * simply call <code>setDestinationOffset(new Point(0, 0))</code> to |
| 535 | * restore default values. |
| 536 | * |
| 537 | * @param destinationOffset the offset in the destination, as a |
| 538 | * <code>Point</code>. |
| 539 | * |
| 540 | * @exception IllegalArgumentException if |
| 541 | * <code>destinationOffset</code> is <code>null</code>. |
| 542 | * |
| 543 | * @see #getDestinationOffset |
| 544 | * @see ImageWriter#replacePixels |
| 545 | */ |
| 546 | public void setDestinationOffset(Point destinationOffset) { |
| 547 | if (destinationOffset == null) { |
| 548 | throw new IllegalArgumentException("destinationOffset == null!"); |
| 549 | } |
| 550 | this.destinationOffset = (Point)destinationOffset.clone(); |
| 551 | } |
| 552 | |
| 553 | /** |
| 554 | * Returns the offset in the destination image at which pixels are |
| 555 | * to be placed. |
| 556 | * |
| 557 | * <p> If <code>setDestinationOffsets</code> has not been called, |
| 558 | * a <code>Point</code> with zero X and Y values is returned |
| 559 | * (which is the correct value). |
| 560 | * |
| 561 | * @return the destination offset as a <code>Point</code>. |
| 562 | * |
| 563 | * @see #setDestinationOffset |
| 564 | */ |
| 565 | public Point getDestinationOffset() { |
| 566 | return (Point)destinationOffset.clone(); |
| 567 | } |
| 568 | |
| 569 | /** |
| 570 | * Sets the <code>IIOParamController</code> to be used |
| 571 | * to provide settings for this <code>IIOParam</code> |
| 572 | * object when the <code>activateController</code> method |
| 573 | * is called, overriding any default controller. If the |
| 574 | * argument is <code>null</code>, no controller will be |
| 575 | * used, including any default. To restore the default, use |
| 576 | * <code>setController(getDefaultController())</code>. |
| 577 | * |
| 578 | * @param controller An appropriate |
| 579 | * <code>IIOParamController</code>, or <code>null</code>. |
| 580 | * |
| 581 | * @see IIOParamController |
| 582 | * @see #getController |
| 583 | * @see #getDefaultController |
| 584 | * @see #hasController |
| 585 | * @see #activateController() |
| 586 | */ |
| 587 | public void setController(IIOParamController controller) { |
| 588 | this.controller = controller; |
| 589 | } |
| 590 | |
| 591 | /** |
| 592 | * Returns whatever <code>IIOParamController</code> is currently |
| 593 | * installed. This could be the default if there is one, |
| 594 | * <code>null</code>, or the argument of the most recent call |
| 595 | * to <code>setController</code>. |
| 596 | * |
| 597 | * @return the currently installed |
| 598 | * <code>IIOParamController</code>, or <code>null</code>. |
| 599 | * |
| 600 | * @see IIOParamController |
| 601 | * @see #setController |
| 602 | * @see #getDefaultController |
| 603 | * @see #hasController |
| 604 | * @see #activateController() |
| 605 | */ |
| 606 | public IIOParamController getController() { |
| 607 | return controller; |
| 608 | } |
| 609 | |
| 610 | /** |
| 611 | * Returns the default <code>IIOParamController</code>, if there |
| 612 | * is one, regardless of the currently installed controller. If |
| 613 | * there is no default controller, returns <code>null</code>. |
| 614 | * |
| 615 | * @return the default <code>IIOParamController</code>, or |
| 616 | * <code>null</code>. |
| 617 | * |
| 618 | * @see IIOParamController |
| 619 | * @see #setController(IIOParamController) |
| 620 | * @see #getController |
| 621 | * @see #hasController |
| 622 | * @see #activateController() |
| 623 | */ |
| 624 | public IIOParamController getDefaultController() { |
| 625 | return defaultController; |
| 626 | } |
| 627 | |
| 628 | /** |
| 629 | * Returns <code>true</code> if there is a controller installed |
| 630 | * for this <code>IIOParam</code> object. This will return |
| 631 | * <code>true</code> if <code>getController</code> would not |
| 632 | * return <code>null</code>. |
| 633 | * |
| 634 | * @return <code>true</code> if a controller is installed. |
| 635 | * |
| 636 | * @see IIOParamController |
| 637 | * @see #setController(IIOParamController) |
| 638 | * @see #getController |
| 639 | * @see #getDefaultController |
| 640 | * @see #activateController() |
| 641 | */ |
| 642 | public boolean hasController() { |
| 643 | return (controller != null); |
| 644 | } |
| 645 | |
| 646 | /** |
| 647 | * Activates the installed <code>IIOParamController</code> for |
| 648 | * this <code>IIOParam</code> object and returns the resulting |
| 649 | * value. When this method returns <code>true</code>, all values |
| 650 | * for this <code>IIOParam</code> object will be ready for the |
| 651 | * next read or write operation. If <code>false</code> is |
| 652 | * returned, no settings in this object will have been disturbed |
| 653 | * (<i>i.e.</i>, the user canceled the operation). |
| 654 | * |
| 655 | * <p> Ordinarily, the controller will be a GUI providing a user |
| 656 | * interface for a subclass of <code>IIOParam</code> for a |
| 657 | * particular plug-in. Controllers need not be GUIs, however. |
| 658 | * |
| 659 | * @return <code>true</code> if the controller completed normally. |
| 660 | * |
| 661 | * @exception IllegalStateException if there is no controller |
| 662 | * currently installed. |
| 663 | * |
| 664 | * @see IIOParamController |
| 665 | * @see #setController(IIOParamController) |
| 666 | * @see #getController |
| 667 | * @see #getDefaultController |
| 668 | * @see #hasController |
| 669 | */ |
| 670 | public boolean activateController() { |
| 671 | if (!hasController()) { |
| 672 | throw new IllegalStateException("hasController() == false!"); |
| 673 | } |
| 674 | return getController().activate(this); |
| 675 | } |
| 676 | } |