J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1998-2006 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 java.awt; |
| 27 | |
| 28 | import java.util.Map; |
| 29 | import java.util.Set; |
| 30 | import java.util.Collection; |
| 31 | import java.util.Collections; |
| 32 | import java.util.HashMap; |
| 33 | import java.util.Iterator; |
| 34 | import sun.awt.SunHints; |
| 35 | import java.lang.ref.WeakReference; |
| 36 | |
| 37 | /** |
| 38 | * The {@code RenderingHints} class defines and manages collections of |
| 39 | * keys and associated values which allow an application to provide input |
| 40 | * into the choice of algorithms used by other classes which perform |
| 41 | * rendering and image manipulation services. |
| 42 | * The {@link java.awt.Graphics2D} class, and classes that implement |
| 43 | * {@link java.awt.image.BufferedImageOp} and |
| 44 | * {@link java.awt.image.RasterOp} all provide methods to get and |
| 45 | * possibly to set individual or groups of {@code RenderingHints} |
| 46 | * keys and their associated values. |
| 47 | * When those implementations perform any rendering or image manipulation |
| 48 | * operations they should examine the values of any {@code RenderingHints} |
| 49 | * that were requested by the caller and tailor the algorithms used |
| 50 | * accordingly and to the best of their ability. |
| 51 | * <p> |
| 52 | * Note that since these keys and values are <i>hints</i>, there is |
| 53 | * no requirement that a given implementation supports all possible |
| 54 | * choices indicated below or that it can respond to requests to |
| 55 | * modify its choice of algorithm. |
| 56 | * The values of the various hint keys may also interact such that |
| 57 | * while all variants of a given key are supported in one situation, |
| 58 | * the implementation may be more restricted when the values associated |
| 59 | * with other keys are modified. |
| 60 | * For example, some implementations may be able to provide several |
| 61 | * types of dithering when the antialiasing hint is turned off, but |
| 62 | * have little control over dithering when antialiasing is on. |
| 63 | * The full set of supported keys and hints may also vary by destination |
| 64 | * since runtimes may use different underlying modules to render to |
| 65 | * the screen, or to {@link java.awt.image.BufferedImage} objects, |
| 66 | * or while printing. |
| 67 | * <p> |
| 68 | * Implementations are free to ignore the hints completely, but should |
| 69 | * try to use an implementation algorithm that is as close as possible |
| 70 | * to the request. |
| 71 | * If an implementation supports a given algorithm when any value is used |
| 72 | * for an associated hint key, then minimally it must do so when the |
| 73 | * value for that key is the exact value that specifies the algorithm. |
| 74 | * <p> |
| 75 | * The keys used to control the hints are all special values that |
| 76 | * subclass the associated {@link RenderingHints.Key} class. |
| 77 | * Many common hints are expressed below as static constants in this |
| 78 | * class, but the list is not meant to be exhaustive. |
| 79 | * Other hints may be created by other packages by defining new objects |
| 80 | * which subclass the {@code Key} class and defining the associated values. |
| 81 | */ |
| 82 | public class RenderingHints |
| 83 | implements Map<Object,Object>, Cloneable |
| 84 | { |
| 85 | /** |
| 86 | * Defines the base type of all keys used along with the |
| 87 | * {@link RenderingHints} class to control various |
| 88 | * algorithm choices in the rendering and imaging pipelines. |
| 89 | * Instances of this class are immutable and unique which |
| 90 | * means that tests for matches can be made using the |
| 91 | * {@code ==} operator instead of the more expensive |
| 92 | * {@code equals()} method. |
| 93 | */ |
| 94 | public abstract static class Key { |
| 95 | private static HashMap identitymap = new HashMap(17); |
| 96 | |
| 97 | private String getIdentity() { |
| 98 | // Note that the identity string is dependent on 3 variables: |
| 99 | // - the name of the subclass of Key |
| 100 | // - the identityHashCode of the subclass of Key |
| 101 | // - the integer key of the Key |
| 102 | // It is theoretically possible for 2 distinct keys to collide |
| 103 | // along all 3 of those attributes in the context of multiple |
| 104 | // class loaders, but that occurence will be extremely rare and |
| 105 | // we account for that possibility below in the recordIdentity |
| 106 | // method by slightly relaxing our uniqueness guarantees if we |
| 107 | // end up in that situation. |
| 108 | return getClass().getName()+"@"+ |
| 109 | Integer.toHexString(System.identityHashCode(getClass()))+":"+ |
| 110 | Integer.toHexString(privatekey); |
| 111 | } |
| 112 | |
| 113 | private synchronized static void recordIdentity(Key k) { |
| 114 | Object identity = k.getIdentity(); |
| 115 | Object otherref = identitymap.get(identity); |
| 116 | if (otherref != null) { |
| 117 | Key otherkey = (Key) ((WeakReference) otherref).get(); |
| 118 | if (otherkey != null && otherkey.getClass() == k.getClass()) { |
| 119 | throw new IllegalArgumentException(identity+ |
| 120 | " already registered"); |
| 121 | } |
| 122 | // Note that this system can fail in a mostly harmless |
| 123 | // way. If we end up generating the same identity |
| 124 | // String for 2 different classes (a very rare case) |
| 125 | // then we correctly avoid throwing the exception above, |
| 126 | // but we are about to drop through to a statement that |
| 127 | // will replace the entry for the old Key subclass with |
| 128 | // an entry for the new Key subclass. At that time the |
| 129 | // old subclass will be vulnerable to someone generating |
| 130 | // a duplicate Key instance for it. We could bail out |
| 131 | // of the method here and let the old identity keep its |
| 132 | // record in the map, but we are more likely to see a |
| 133 | // duplicate key go by for the new class than the old |
| 134 | // one since the new one is probably still in the |
| 135 | // initialization stage. In either case, the probability |
| 136 | // of loading 2 classes in the same VM with the same name |
| 137 | // and identityHashCode should be nearly impossible. |
| 138 | } |
| 139 | // Note: Use a weak reference to avoid holding on to extra |
| 140 | // objects and classes after they should be unloaded. |
| 141 | identitymap.put(identity, new WeakReference(k)); |
| 142 | } |
| 143 | |
| 144 | private int privatekey; |
| 145 | |
| 146 | /** |
| 147 | * Construct a key using the indicated private key. Each |
| 148 | * subclass of Key maintains its own unique domain of integer |
| 149 | * keys. No two objects with the same integer key and of the |
| 150 | * same specific subclass can be constructed. An exception |
| 151 | * will be thrown if an attempt is made to construct another |
| 152 | * object of a given class with the same integer key as a |
| 153 | * pre-existing instance of that subclass of Key. |
| 154 | * @param privatekey the specified key |
| 155 | */ |
| 156 | protected Key(int privatekey) { |
| 157 | this.privatekey = privatekey; |
| 158 | recordIdentity(this); |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * Returns true if the specified object is a valid value |
| 163 | * for this Key. |
| 164 | * @param val the <code>Object</code> to test for validity |
| 165 | * @return <code>true</code> if <code>val</code> is valid; |
| 166 | * <code>false</code> otherwise. |
| 167 | */ |
| 168 | public abstract boolean isCompatibleValue(Object val); |
| 169 | |
| 170 | /** |
| 171 | * Returns the private integer key that the subclass |
| 172 | * instantiated this Key with. |
| 173 | * @return the private integer key that the subclass |
| 174 | * instantiated this Key with. |
| 175 | */ |
| 176 | protected final int intKey() { |
| 177 | return privatekey; |
| 178 | } |
| 179 | |
| 180 | /** |
| 181 | * The hash code for all Key objects will be the same as the |
| 182 | * system identity code of the object as defined by the |
| 183 | * System.identityHashCode() method. |
| 184 | */ |
| 185 | public final int hashCode() { |
| 186 | return super.hashCode(); |
| 187 | } |
| 188 | |
| 189 | /** |
| 190 | * The equals method for all Key objects will return the same |
| 191 | * result as the equality operator '=='. |
| 192 | */ |
| 193 | public final boolean equals(Object o) { |
| 194 | return this == o; |
| 195 | } |
| 196 | } |
| 197 | |
| 198 | HashMap hintmap = new HashMap(7); |
| 199 | |
| 200 | /** |
| 201 | * Antialiasing hint key. |
| 202 | * The {@code ANTIALIASING} hint controls whether or not the |
| 203 | * geometry rendering methods of a {@link Graphics2D} object |
| 204 | * will attempt to reduce aliasing artifacts along the edges |
| 205 | * of shapes. |
| 206 | * <p> |
| 207 | * A typical antialiasing algorithm works by blending the existing |
| 208 | * colors of the pixels along the boundary of a shape with the |
| 209 | * requested fill paint according to the estimated partial pixel |
| 210 | * coverage of the shape. |
| 211 | * <p> |
| 212 | * The allowable values for this hint are |
| 213 | * <ul> |
| 214 | * <li>{@link #VALUE_ANTIALIAS_ON} |
| 215 | * <li>{@link #VALUE_ANTIALIAS_OFF} |
| 216 | * <li>{@link #VALUE_ANTIALIAS_DEFAULT} |
| 217 | * </ul> |
| 218 | */ |
| 219 | public static final Key KEY_ANTIALIASING = |
| 220 | SunHints.KEY_ANTIALIASING; |
| 221 | |
| 222 | /** |
| 223 | * Antialiasing hint value -- rendering is done with antialiasing. |
| 224 | * @see #KEY_ANTIALIASING |
| 225 | */ |
| 226 | public static final Object VALUE_ANTIALIAS_ON = |
| 227 | SunHints.VALUE_ANTIALIAS_ON; |
| 228 | |
| 229 | /** |
| 230 | * Antialiasing hint value -- rendering is done without antialiasing. |
| 231 | * @see #KEY_ANTIALIASING |
| 232 | */ |
| 233 | public static final Object VALUE_ANTIALIAS_OFF = |
| 234 | SunHints.VALUE_ANTIALIAS_OFF; |
| 235 | |
| 236 | /** |
| 237 | * Antialiasing hint value -- rendering is done with a default |
| 238 | * antialiasing mode chosen by the implementation. |
| 239 | * @see #KEY_ANTIALIASING |
| 240 | */ |
| 241 | public static final Object VALUE_ANTIALIAS_DEFAULT = |
| 242 | SunHints.VALUE_ANTIALIAS_DEFAULT; |
| 243 | |
| 244 | /** |
| 245 | * Rendering hint key. |
| 246 | * The {@code RENDERING} hint is a general hint that provides |
| 247 | * a high level recommendation as to whether to bias algorithm |
| 248 | * choices more for speed or quality when evaluating tradeoffs. |
| 249 | * This hint could be consulted for any rendering or image |
| 250 | * manipulation operation, but decisions will usually honor |
| 251 | * other, more specific hints in preference to this hint. |
| 252 | * <p> |
| 253 | * The allowable values for this hint are |
| 254 | * <ul> |
| 255 | * <li>{@link #VALUE_RENDER_SPEED} |
| 256 | * <li>{@link #VALUE_RENDER_QUALITY} |
| 257 | * <li>{@link #VALUE_RENDER_DEFAULT} |
| 258 | * </ul> |
| 259 | */ |
| 260 | public static final Key KEY_RENDERING = |
| 261 | SunHints.KEY_RENDERING; |
| 262 | |
| 263 | /** |
| 264 | * Rendering hint value -- rendering algorithms are chosen |
| 265 | * with a preference for output speed. |
| 266 | * @see #KEY_RENDERING |
| 267 | */ |
| 268 | public static final Object VALUE_RENDER_SPEED = |
| 269 | SunHints.VALUE_RENDER_SPEED; |
| 270 | |
| 271 | /** |
| 272 | * Rendering hint value -- rendering algorithms are chosen |
| 273 | * with a preference for output quality. |
| 274 | * @see #KEY_RENDERING |
| 275 | */ |
| 276 | public static final Object VALUE_RENDER_QUALITY = |
| 277 | SunHints.VALUE_RENDER_QUALITY; |
| 278 | |
| 279 | /** |
| 280 | * Rendering hint value -- rendering algorithms are chosen |
| 281 | * by the implementation for a good tradeoff of performance |
| 282 | * vs. quality. |
| 283 | * @see #KEY_RENDERING |
| 284 | */ |
| 285 | public static final Object VALUE_RENDER_DEFAULT = |
| 286 | SunHints.VALUE_RENDER_DEFAULT; |
| 287 | |
| 288 | /** |
| 289 | * Dithering hint key. |
| 290 | * The {@code DITHERING} hint controls how closely to approximate |
| 291 | * a color when storing into a destination with limited color |
| 292 | * resolution. |
| 293 | * <p> |
| 294 | * Some rendering destinations may support a limited number of |
| 295 | * color choices which may not be able to accurately represent |
| 296 | * the full spectrum of colors that can result during rendering |
| 297 | * operations. |
| 298 | * For such a destination the {@code DITHERING} hint controls |
| 299 | * whether rendering is done with a flat solid fill of a single |
| 300 | * pixel value which is the closest supported color to what was |
| 301 | * requested, or whether shapes will be filled with a pattern of |
| 302 | * colors which combine to better approximate that color. |
| 303 | * <p> |
| 304 | * The allowable values for this hint are |
| 305 | * <ul> |
| 306 | * <li>{@link #VALUE_DITHER_DISABLE} |
| 307 | * <li>{@link #VALUE_DITHER_ENABLE} |
| 308 | * <li>{@link #VALUE_DITHER_DEFAULT} |
| 309 | * </ul> |
| 310 | */ |
| 311 | public static final Key KEY_DITHERING = |
| 312 | SunHints.KEY_DITHERING; |
| 313 | |
| 314 | /** |
| 315 | * Dithering hint value -- do not dither when rendering geometry. |
| 316 | * @see #KEY_DITHERING |
| 317 | */ |
| 318 | public static final Object VALUE_DITHER_DISABLE = |
| 319 | SunHints.VALUE_DITHER_DISABLE; |
| 320 | |
| 321 | /** |
| 322 | * Dithering hint value -- dither when rendering geometry, if needed. |
| 323 | * @see #KEY_DITHERING |
| 324 | */ |
| 325 | public static final Object VALUE_DITHER_ENABLE = |
| 326 | SunHints.VALUE_DITHER_ENABLE; |
| 327 | |
| 328 | /** |
| 329 | * Dithering hint value -- use a default for dithering chosen by |
| 330 | * the implementation. |
| 331 | * @see #KEY_DITHERING |
| 332 | */ |
| 333 | public static final Object VALUE_DITHER_DEFAULT = |
| 334 | SunHints.VALUE_DITHER_DEFAULT; |
| 335 | |
| 336 | /** |
| 337 | * Text antialiasing hint key. |
| 338 | * The {@code TEXT_ANTIALIASING} hint can control the use of |
| 339 | * antialiasing algorithms for text independently of the |
| 340 | * choice used for shape rendering. |
| 341 | * Often an application may want to use antialiasing for text |
| 342 | * only and not for other shapes. |
| 343 | * Additionally, the algorithms for reducing the aliasing |
| 344 | * artifacts for text are often more sophisticated than those |
| 345 | * that have been developed for general rendering so this |
| 346 | * hint key provides additional values which can control |
| 347 | * the choices of some of those text-specific algorithms. |
| 348 | * If left in the {@code DEFAULT} state, this hint will |
| 349 | * generally defer to the value of the regular |
| 350 | * {@link #KEY_ANTIALIASING} hint key. |
| 351 | * <p> |
| 352 | * The allowable values for this hint are |
| 353 | * <ul> |
| 354 | * <li>{@link #VALUE_TEXT_ANTIALIAS_ON} |
| 355 | * <li>{@link #VALUE_TEXT_ANTIALIAS_OFF} |
| 356 | * <li>{@link #VALUE_TEXT_ANTIALIAS_DEFAULT} |
| 357 | * <li>{@link #VALUE_TEXT_ANTIALIAS_GASP} |
| 358 | * <li>{@link #VALUE_TEXT_ANTIALIAS_LCD_HRGB} |
| 359 | * <li>{@link #VALUE_TEXT_ANTIALIAS_LCD_HBGR} |
| 360 | * <li>{@link #VALUE_TEXT_ANTIALIAS_LCD_VRGB} |
| 361 | * <li>{@link #VALUE_TEXT_ANTIALIAS_LCD_VBGR} |
| 362 | * </ul> |
| 363 | */ |
| 364 | public static final Key KEY_TEXT_ANTIALIASING = |
| 365 | SunHints.KEY_TEXT_ANTIALIASING; |
| 366 | |
| 367 | /** |
| 368 | * Text antialiasing hint value -- text rendering is done with |
| 369 | * some form of antialiasing. |
| 370 | * @see #KEY_TEXT_ANTIALIASING |
| 371 | */ |
| 372 | public static final Object VALUE_TEXT_ANTIALIAS_ON = |
| 373 | SunHints.VALUE_TEXT_ANTIALIAS_ON; |
| 374 | |
| 375 | /** |
| 376 | * Text antialiasing hint value -- text rendering is done without |
| 377 | * any form of antialiasing. |
| 378 | * @see #KEY_TEXT_ANTIALIASING |
| 379 | */ |
| 380 | public static final Object VALUE_TEXT_ANTIALIAS_OFF = |
| 381 | SunHints.VALUE_TEXT_ANTIALIAS_OFF; |
| 382 | |
| 383 | /** |
| 384 | * Text antialiasing hint value -- text rendering is done according |
| 385 | * to the {@link #KEY_ANTIALIASING} hint or a default chosen by the |
| 386 | * implementation. |
| 387 | * @see #KEY_TEXT_ANTIALIASING |
| 388 | */ |
| 389 | public static final Object VALUE_TEXT_ANTIALIAS_DEFAULT = |
| 390 | SunHints.VALUE_TEXT_ANTIALIAS_DEFAULT; |
| 391 | |
| 392 | /** |
| 393 | * Text antialiasing hint value -- text rendering is requested to |
| 394 | * use information in the font resource which specifies for each point |
| 395 | * size whether to apply {@link #VALUE_TEXT_ANTIALIAS_ON} or |
| 396 | * {@link #VALUE_TEXT_ANTIALIAS_OFF}. |
| 397 | * <p> |
| 398 | * TrueType fonts typically provide this information in the 'gasp' table. |
| 399 | * In the absence of this information, the behaviour for a particular |
| 400 | * font and size is determined by implementation defaults. |
| 401 | * <p> |
| 402 | * <i>Note:</i>A font designer will typically carefully hint a font for |
| 403 | * the most common user interface point sizes. Consequently the 'gasp' |
| 404 | * table will likely specify to use only hinting at those sizes and not |
| 405 | * "smoothing". So in many cases the resulting text display is |
| 406 | * equivalent to {@code VALUE_TEXT_ANTIALIAS_OFF}. |
| 407 | * This may be unexpected but is correct. |
| 408 | * <p> |
| 409 | * Logical fonts which are composed of multiple physical fonts will for |
| 410 | * consistency will use the setting most appropriate for the overall |
| 411 | * composite font. |
| 412 | * |
| 413 | * @see #KEY_TEXT_ANTIALIASING |
| 414 | * @since 1.6 |
| 415 | */ |
| 416 | public static final Object VALUE_TEXT_ANTIALIAS_GASP = |
| 417 | SunHints.VALUE_TEXT_ANTIALIAS_GASP; |
| 418 | |
| 419 | /** |
| 420 | * Text antialiasing hint value -- request that text be displayed |
| 421 | * optimised for an LCD display with subpixels in order from display |
| 422 | * left to right of R,G,B such that the horizontal subpixel resolution |
| 423 | * is three times that of the full pixel horizontal resolution (HRGB). |
| 424 | * This is the most common configuration. |
| 425 | * Selecting this hint for displays with one of the other LCD subpixel |
| 426 | * configurations will likely result in unfocused text. |
| 427 | * <p> |
| 428 | * <i>Notes:</i><br> |
| 429 | * An implementation when choosing whether to apply any of the |
| 430 | * LCD text hint values may take into account factors including requiring |
| 431 | * color depth of the destination to be at least 15 bits per pixel |
| 432 | * (ie 5 bits per color component), |
| 433 | * characteristics of a font such as whether embedded bitmaps may |
| 434 | * produce better results, or when displaying to a non-local networked |
| 435 | * display device enabling it only if suitable protocols are available, |
| 436 | * or ignoring the hint if performing very high resolution rendering |
| 437 | * or the target device is not appropriate: eg when printing. |
| 438 | * <p> |
| 439 | * These hints can equally be applied when rendering to software images, |
| 440 | * but these images may not then be suitable for general export, as the |
| 441 | * text will have been rendered appropriately for a specific subpixel |
| 442 | * organisation. Also lossy images are not a good choice, nor image |
| 443 | * formats such as GIF which have limited colors. |
| 444 | * So unless the image is destined solely for rendering on a |
| 445 | * display device with the same configuration, some other text |
| 446 | * anti-aliasing hint such as |
| 447 | * {@link #VALUE_TEXT_ANTIALIAS_ON} |
| 448 | * may be a better choice. |
| 449 | * <p>Selecting a value which does not match the LCD display in use |
| 450 | * will likely lead to a degradation in text quality. |
| 451 | * On display devices (ie CRTs) which do not have the same characteristics |
| 452 | * as LCD displays, the overall effect may appear similar to standard text |
| 453 | * anti-aliasing, but the quality may be degraded by color distortion. |
| 454 | * Analog connected LCD displays may also show little advantage over |
| 455 | * standard text-antialiasing and be similar to CRTs. |
| 456 | * <p> |
| 457 | * In other words for the best results use an LCD display with a digital |
| 458 | * display connector and specify the appropriate sub-pixel configuration. |
| 459 | * |
| 460 | * @see #KEY_TEXT_ANTIALIASING |
| 461 | * @since 1.6 |
| 462 | */ |
| 463 | public static final Object VALUE_TEXT_ANTIALIAS_LCD_HRGB = |
| 464 | SunHints.VALUE_TEXT_ANTIALIAS_LCD_HRGB; |
| 465 | |
| 466 | /** |
| 467 | * Text antialiasing hint value -- request that text be displayed |
| 468 | * optimised for an LCD display with subpixels in order from display |
| 469 | * left to right of B,G,R such that the horizontal subpixel resolution |
| 470 | * is three times that of the full pixel horizontal resolution (HBGR). |
| 471 | * This is a much less common configuration than HRGB. |
| 472 | * Selecting this hint for displays with one of the other LCD subpixel |
| 473 | * configurations will likely result in unfocused text. |
| 474 | * See {@link #VALUE_TEXT_ANTIALIAS_LCD_HRGB}, |
| 475 | * for more information on when this hint is applied. |
| 476 | * |
| 477 | * @see #KEY_TEXT_ANTIALIASING |
| 478 | * @since 1.6 |
| 479 | */ |
| 480 | public static final Object VALUE_TEXT_ANTIALIAS_LCD_HBGR = |
| 481 | SunHints.VALUE_TEXT_ANTIALIAS_LCD_HBGR; |
| 482 | |
| 483 | /** |
| 484 | * Text antialiasing hint value -- request that text be displayed |
| 485 | * optimised for an LCD display with subpixel organisation from display |
| 486 | * top to bottom of R,G,B such that the vertical subpixel resolution is |
| 487 | * three times that of the full pixel vertical resolution (VRGB). |
| 488 | * Vertical orientation is very uncommon and probably mainly useful |
| 489 | * for a physically rotated display. |
| 490 | * Selecting this hint for displays with one of the other LCD subpixel |
| 491 | * configurations will likely result in unfocused text. |
| 492 | * See {@link #VALUE_TEXT_ANTIALIAS_LCD_HRGB}, |
| 493 | * for more information on when this hint is applied. |
| 494 | * |
| 495 | * @see #KEY_TEXT_ANTIALIASING |
| 496 | * @since 1.6 |
| 497 | */ |
| 498 | public static final Object VALUE_TEXT_ANTIALIAS_LCD_VRGB = |
| 499 | SunHints.VALUE_TEXT_ANTIALIAS_LCD_VRGB; |
| 500 | |
| 501 | /** |
| 502 | * Text antialiasing hint value -- request that text be displayed |
| 503 | * optimised for an LCD display with subpixel organisation from display |
| 504 | * top to bottom of B,G,R such that the vertical subpixel resolution is |
| 505 | * three times that of the full pixel vertical resolution (VBGR). |
| 506 | * Vertical orientation is very uncommon and probably mainly useful |
| 507 | * for a physically rotated display. |
| 508 | * Selecting this hint for displays with one of the other LCD subpixel |
| 509 | * configurations will likely result in unfocused text. |
| 510 | * See {@link #VALUE_TEXT_ANTIALIAS_LCD_HRGB}, |
| 511 | * for more information on when this hint is applied. |
| 512 | * |
| 513 | * @see #KEY_TEXT_ANTIALIASING |
| 514 | * @since 1.6 |
| 515 | */ |
| 516 | public static final Object VALUE_TEXT_ANTIALIAS_LCD_VBGR = |
| 517 | SunHints.VALUE_TEXT_ANTIALIAS_LCD_VBGR; |
| 518 | |
| 519 | |
| 520 | /** |
| 521 | * LCD text contrast rendering hint key. |
| 522 | * The value is an <code>Integer</code> object which is used as a text |
| 523 | * contrast adjustment when used in conjunction with an LCD text |
| 524 | * anti-aliasing hint such as |
| 525 | * {@link #VALUE_TEXT_ANTIALIAS_LCD_HRGB}. |
| 526 | * <ul> |
| 527 | * <li>Values should be a positive integer in the range 100 to 250. |
| 528 | * <li>A lower value (eg 100) corresponds to higher contrast text when |
| 529 | * displaying dark text on a light background. |
| 530 | * <li>A higher value (eg 200) corresponds to lower contrast text when |
| 531 | * displaying dark text on a light background. |
| 532 | * <li>A typical useful value is in the narrow range 140-180. |
| 533 | * <li>If no value is specified, a system or implementation default value |
| 534 | * will be applied. |
| 535 | * </ul> |
| 536 | * The default value can be expected to be adequate for most purposes, |
| 537 | * so clients should rarely need to specify a value for this hint unless |
| 538 | * they have concrete information as to an appropriate value. |
| 539 | * A higher value does not mean a higher contrast, in fact the opposite |
| 540 | * is true. |
| 541 | * The correction is applied in a similar manner to a gamma adjustment |
| 542 | * for non-linear perceptual luminance response of display systems, but |
| 543 | * does not indicate a full correction for this. |
| 544 | * |
| 545 | * @see #KEY_TEXT_ANTIALIASING |
| 546 | * @since 1.6 |
| 547 | */ |
| 548 | public static final Key KEY_TEXT_LCD_CONTRAST = |
| 549 | SunHints.KEY_TEXT_ANTIALIAS_LCD_CONTRAST; |
| 550 | |
| 551 | /** |
| 552 | * Font fractional metrics hint key. |
| 553 | * The {@code FRACTIONALMETRICS} hint controls whether the positioning |
| 554 | * of individual character glyphs takes into account the sub-pixel |
| 555 | * accuracy of the scaled character advances of the font or whether |
| 556 | * such advance vectors are rounded to an integer number of whole |
| 557 | * device pixels. |
| 558 | * This hint only recommends how much accuracy should be used to |
| 559 | * position the glyphs and does not specify or recommend whether or |
| 560 | * not the actual rasterization or pixel bounds of the glyph should |
| 561 | * be modified to match. |
| 562 | * <p> |
| 563 | * Rendering text to a low resolution device like a screen will |
| 564 | * necessarily involve a number of rounding operations as the |
| 565 | * high quality and very precise definition of the shape and |
| 566 | * metrics of the character glyphs must be matched to discrete |
| 567 | * device pixels. |
| 568 | * Ideally the positioning of glyphs during text layout would be |
| 569 | * calculated by scaling the design metrics in the font according |
| 570 | * to the point size, but then the scaled advance width will not |
| 571 | * necessarily be an integer number of pixels. |
| 572 | * If the glyphs are positioned with sub-pixel accuracy according |
| 573 | * to these scaled design metrics then the rasterization would |
| 574 | * ideally need to be adjusted for each possible sub-pixel origin. |
| 575 | * <p> |
| 576 | * Unfortunately, scaling each glyph customized to its exact |
| 577 | * subpixel origin during text layout would be prohibitively |
| 578 | * expensive so a simplified system based on integer device |
| 579 | * positions is typically used to lay out the text. |
| 580 | * The rasterization of the glyph and the scaled advance width |
| 581 | * are both adjusted together to yield text that looks good at |
| 582 | * device resolution and has consistent integer pixel distances |
| 583 | * between glyphs that help the glyphs look uniformly and |
| 584 | * consistently spaced and readable. |
| 585 | * <p> |
| 586 | * This process of rounding advance widths for rasterized glyphs |
| 587 | * to integer distances means that the character density and the |
| 588 | * overall length of a string of text will be different from the |
| 589 | * theoretical design measurements due to the accumulation of |
| 590 | * a series of small differences in the adjusted widths of |
| 591 | * each glyph. |
| 592 | * The specific differences will be different for each glyph, |
| 593 | * some being wider and some being narrower than their theoretical |
| 594 | * design measurements. |
| 595 | * Thus the overall difference in character density and length |
| 596 | * will vary by a number of factors including the font, the |
| 597 | * specific device resolution being targeted, and the glyphs |
| 598 | * chosen to represent the string being rendered. |
| 599 | * As a result, rendering the same string at multiple device |
| 600 | * resolutions can yield widely varying metrics for whole strings. |
| 601 | * <p> |
| 602 | * When {@code FRACTIONALMETRICS} are enabled, the true font design |
| 603 | * metrics are scaled by the point size and used for layout with |
| 604 | * sub-pixel accuracy. |
| 605 | * The average density of glyphs and total length of a long |
| 606 | * string of characters will therefore more closely match the |
| 607 | * theoretical design of the font, but readability may be affected |
| 608 | * since individual pairs of characters may not always appear to |
| 609 | * be consistent distances apart depending on how the sub-pixel |
| 610 | * accumulation of the glyph origins meshes with the device pixel |
| 611 | * grid. |
| 612 | * Enabling this hint may be desirable when text layout is being |
| 613 | * performed that must be consistent across a wide variety of |
| 614 | * output resolutions. |
| 615 | * Specifically, this hint may be desirable in situations where |
| 616 | * the layout of text is being previewed on a low resolution |
| 617 | * device like a screen for output that will eventually be |
| 618 | * rendered on a high resolution printer or typesetting device. |
| 619 | * <p> |
| 620 | * When disabled, the scaled design metrics are rounded or adjusted |
| 621 | * to integer distances for layout. |
| 622 | * The distances between any specific pair of glyphs will be more |
| 623 | * uniform on the device, but the density and total length of long |
| 624 | * strings may no longer match the theoretical intentions of the |
| 625 | * font designer. |
| 626 | * Disabling this hint will typically produce more readable results |
| 627 | * on low resolution devices like computer monitors. |
| 628 | * <p> |
| 629 | * The allowable values for this key are |
| 630 | * <ul> |
| 631 | * <li>{@link #VALUE_FRACTIONALMETRICS_OFF} |
| 632 | * <li>{@link #VALUE_FRACTIONALMETRICS_ON} |
| 633 | * <li>{@link #VALUE_FRACTIONALMETRICS_DEFAULT} |
| 634 | * </ul> |
| 635 | */ |
| 636 | public static final Key KEY_FRACTIONALMETRICS = |
| 637 | SunHints.KEY_FRACTIONALMETRICS; |
| 638 | |
| 639 | /** |
| 640 | * Font fractional metrics hint value -- character glyphs are |
| 641 | * positioned with advance widths rounded to pixel boundaries. |
| 642 | * @see #KEY_FRACTIONALMETRICS |
| 643 | */ |
| 644 | public static final Object VALUE_FRACTIONALMETRICS_OFF = |
| 645 | SunHints.VALUE_FRACTIONALMETRICS_OFF; |
| 646 | |
| 647 | /** |
| 648 | * Font fractional metrics hint value -- character glyphs are |
| 649 | * positioned with sub-pixel accuracy. |
| 650 | * @see #KEY_FRACTIONALMETRICS |
| 651 | */ |
| 652 | public static final Object VALUE_FRACTIONALMETRICS_ON = |
| 653 | SunHints.VALUE_FRACTIONALMETRICS_ON; |
| 654 | |
| 655 | /** |
| 656 | * Font fractional metrics hint value -- character glyphs are |
| 657 | * positioned with accuracy chosen by the implementation. |
| 658 | * @see #KEY_FRACTIONALMETRICS |
| 659 | */ |
| 660 | public static final Object VALUE_FRACTIONALMETRICS_DEFAULT = |
| 661 | SunHints.VALUE_FRACTIONALMETRICS_DEFAULT; |
| 662 | |
| 663 | /** |
| 664 | * Interpolation hint key. |
| 665 | * The {@code INTERPOLATION} hint controls how image pixels are |
| 666 | * filtered or resampled during an image rendering operation. |
| 667 | * <p> |
| 668 | * Implicitly images are defined to provide color samples at |
| 669 | * integer coordinate locations. |
| 670 | * When images are rendered upright with no scaling onto a |
| 671 | * destination, the choice of which image pixels map to which |
| 672 | * device pixels is obvious and the samples at the integer |
| 673 | * coordinate locations in the image are transfered to the |
| 674 | * pixels at the corresponding integer locations on the device |
| 675 | * pixel grid one for one. |
| 676 | * When images are rendered in a scaled, rotated, or otherwise |
| 677 | * transformed coordinate system, then the mapping of device |
| 678 | * pixel coordinates back to the image can raise the question |
| 679 | * of what color sample to use for the continuous coordinates |
| 680 | * that lie between the integer locations of the provided image |
| 681 | * samples. |
| 682 | * Interpolation algorithms define functions which provide a |
| 683 | * color sample for any continuous coordinate in an image based |
| 684 | * on the color samples at the surrounding integer coordinates. |
| 685 | * <p> |
| 686 | * The allowable values for this hint are |
| 687 | * <ul> |
| 688 | * <li>{@link #VALUE_INTERPOLATION_NEAREST_NEIGHBOR} |
| 689 | * <li>{@link #VALUE_INTERPOLATION_BILINEAR} |
| 690 | * <li>{@link #VALUE_INTERPOLATION_BICUBIC} |
| 691 | * </ul> |
| 692 | */ |
| 693 | public static final Key KEY_INTERPOLATION = |
| 694 | SunHints.KEY_INTERPOLATION; |
| 695 | |
| 696 | /** |
| 697 | * Interpolation hint value -- the color sample of the nearest |
| 698 | * neighboring integer coordinate sample in the image is used. |
| 699 | * Conceptually the image is viewed as a grid of unit-sized |
| 700 | * square regions of color centered around the center of each |
| 701 | * image pixel. |
| 702 | * <p> |
| 703 | * As the image is scaled up, it will look correspondingly blocky. |
| 704 | * As the image is scaled down, the colors for source pixels will |
| 705 | * be either used unmodified, or skipped entirely in the output |
| 706 | * representation. |
| 707 | * |
| 708 | * @see #KEY_INTERPOLATION |
| 709 | */ |
| 710 | public static final Object VALUE_INTERPOLATION_NEAREST_NEIGHBOR = |
| 711 | SunHints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR; |
| 712 | |
| 713 | /** |
| 714 | * Interpolation hint value -- the color samples of the 4 nearest |
| 715 | * neighboring integer coordinate samples in the image are |
| 716 | * interpolated linearly to produce a color sample. |
| 717 | * Conceptually the image is viewed as a set of infinitely small |
| 718 | * point color samples which have value only at the centers of |
| 719 | * integer coordinate pixels and the space between those pixel |
| 720 | * centers is filled with linear ramps of colors that connect |
| 721 | * adjacent discrete samples in a straight line. |
| 722 | * <p> |
| 723 | * As the image is scaled up, there are no blocky edges between |
| 724 | * the colors in the image as there are with |
| 725 | * {@link #VALUE_INTERPOLATION_NEAREST_NEIGHBOR NEAREST_NEIGHBOR}, |
| 726 | * but the blending may show some subtle discontinuities along the |
| 727 | * horizontal and vertical edges that line up with the samples |
| 728 | * caused by a sudden change in the slope of the interpolation |
| 729 | * from one side of a sample to the other. |
| 730 | * As the image is scaled down, more image pixels have their |
| 731 | * color samples represented in the resulting output since each |
| 732 | * output pixel recieves color information from up to 4 image |
| 733 | * pixels. |
| 734 | * |
| 735 | * @see #KEY_INTERPOLATION |
| 736 | */ |
| 737 | public static final Object VALUE_INTERPOLATION_BILINEAR = |
| 738 | SunHints.VALUE_INTERPOLATION_BILINEAR; |
| 739 | |
| 740 | /** |
| 741 | * Interpolation hint value -- the color samples of 9 nearby |
| 742 | * integer coordinate samples in the image are interpolated using |
| 743 | * a cubic function in both {@code X} and {@code Y} to produce |
| 744 | * a color sample. |
| 745 | * Conceptually the view of the image is very similar to the view |
| 746 | * used in the {@link #VALUE_INTERPOLATION_BILINEAR BILINEAR} |
| 747 | * algorithm except that the ramps of colors that connect between |
| 748 | * the samples are curved and have better continuity of slope |
| 749 | * as they cross over between sample boundaries. |
| 750 | * <p> |
| 751 | * As the image is scaled up, there are no blocky edges and the |
| 752 | * interpolation should appear smoother and with better depictions |
| 753 | * of any edges in the original image than with {@code BILINEAR}. |
| 754 | * As the image is scaled down, even more of the original color |
| 755 | * samples from the original image will have their color information |
| 756 | * carried through and represented. |
| 757 | * |
| 758 | * @see #KEY_INTERPOLATION |
| 759 | */ |
| 760 | public static final Object VALUE_INTERPOLATION_BICUBIC = |
| 761 | SunHints.VALUE_INTERPOLATION_BICUBIC; |
| 762 | |
| 763 | /** |
| 764 | * Alpha interpolation hint key. |
| 765 | * The {@code ALPHA_INTERPOLATION} hint is a general hint that |
| 766 | * provides a high level recommendation as to whether to bias |
| 767 | * alpha blending algorithm choices more for speed or quality |
| 768 | * when evaluating tradeoffs. |
| 769 | * <p> |
| 770 | * This hint could control the choice of alpha blending |
| 771 | * calculations that sacrifice some precision to use fast |
| 772 | * lookup tables or lower precision SIMD instructions. |
| 773 | * This hint could also control whether or not the color |
| 774 | * and alpha values are converted into a linear color space |
| 775 | * during the calculations for a more linear visual effect |
| 776 | * at the expense of additional per-pixel calculations. |
| 777 | * <p> |
| 778 | * The allowable values for this hint are |
| 779 | * <ul> |
| 780 | * <li>{@link #VALUE_ALPHA_INTERPOLATION_SPEED} |
| 781 | * <li>{@link #VALUE_ALPHA_INTERPOLATION_QUALITY} |
| 782 | * <li>{@link #VALUE_ALPHA_INTERPOLATION_DEFAULT} |
| 783 | * </ul> |
| 784 | */ |
| 785 | public static final Key KEY_ALPHA_INTERPOLATION = |
| 786 | SunHints.KEY_ALPHA_INTERPOLATION; |
| 787 | |
| 788 | /** |
| 789 | * Alpha interpolation hint value -- alpha blending algorithms |
| 790 | * are chosen with a preference for calculation speed. |
| 791 | * @see #KEY_ALPHA_INTERPOLATION |
| 792 | */ |
| 793 | public static final Object VALUE_ALPHA_INTERPOLATION_SPEED = |
| 794 | SunHints.VALUE_ALPHA_INTERPOLATION_SPEED; |
| 795 | |
| 796 | /** |
| 797 | * Alpha interpolation hint value -- alpha blending algorithms |
| 798 | * are chosen with a preference for precision and visual quality. |
| 799 | * @see #KEY_ALPHA_INTERPOLATION |
| 800 | */ |
| 801 | public static final Object VALUE_ALPHA_INTERPOLATION_QUALITY = |
| 802 | SunHints.VALUE_ALPHA_INTERPOLATION_QUALITY; |
| 803 | |
| 804 | /** |
| 805 | * Alpha interpolation hint value -- alpha blending algorithms |
| 806 | * are chosen by the implementation for a good tradeoff of |
| 807 | * performance vs. quality. |
| 808 | * @see #KEY_ALPHA_INTERPOLATION |
| 809 | */ |
| 810 | public static final Object VALUE_ALPHA_INTERPOLATION_DEFAULT = |
| 811 | SunHints.VALUE_ALPHA_INTERPOLATION_DEFAULT; |
| 812 | |
| 813 | /** |
| 814 | * Color rendering hint key. |
| 815 | * The {@code COLOR_RENDERING} hint controls the accuracy of |
| 816 | * approximation and conversion when storing colors into a |
| 817 | * destination image or surface. |
| 818 | * <p> |
| 819 | * When a rendering or image manipulation operation produces |
| 820 | * a color value that must be stored into a destination, it |
| 821 | * must first convert that color into a form suitable for |
| 822 | * storing into the destination image or surface. |
| 823 | * Minimally, the color components must be converted to bit |
| 824 | * representations and ordered in the correct order or an |
| 825 | * index into a color lookup table must be chosen before |
| 826 | * the data can be stored into the destination memory. |
| 827 | * Without this minimal conversion, the data in the destination |
| 828 | * would likely represent random, incorrect or possibly even |
| 829 | * unsupported values. |
| 830 | * Algorithms to quickly convert the results of rendering |
| 831 | * operations into the color format of most common destinations |
| 832 | * are well known and fairly optimal to execute. |
| 833 | * <p> |
| 834 | * Simply performing the most basic color format conversion to |
| 835 | * store colors into a destination can potentially ignore a |
| 836 | * difference in the calibration of the |
| 837 | * {@link java.awt.color.ColorSpace} |
| 838 | * of the source and destination or other factors such as the |
| 839 | * linearity of the gamma correction. |
| 840 | * Unless the source and destination {@code ColorSpace} are |
| 841 | * identical, to correctly perform a rendering operation with |
| 842 | * the most care taken for the accuracy of the colors being |
| 843 | * represented, the source colors should be converted to a |
| 844 | * device independent {@code ColorSpace} and the results then |
| 845 | * converted back to the destination {@code ColorSpace}. |
| 846 | * Furthermore, if calculations such as the blending of multiple |
| 847 | * source colors are to be performed during the rendering |
| 848 | * operation, greater visual clarity can be achieved if the |
| 849 | * intermediate device independent {@code ColorSpace} is |
| 850 | * chosen to have a linear relationship between the values |
| 851 | * being calculated and the perception of the human eye to |
| 852 | * the response curves of the output device. |
| 853 | * <p> |
| 854 | * The allowable values for this hint are |
| 855 | * <ul> |
| 856 | * <li>{@link #VALUE_COLOR_RENDER_SPEED} |
| 857 | * <li>{@link #VALUE_COLOR_RENDER_QUALITY} |
| 858 | * <li>{@link #VALUE_COLOR_RENDER_DEFAULT} |
| 859 | * </ul> |
| 860 | */ |
| 861 | public static final Key KEY_COLOR_RENDERING = |
| 862 | SunHints.KEY_COLOR_RENDERING; |
| 863 | |
| 864 | /** |
| 865 | * Color rendering hint value -- perform the fastest color |
| 866 | * conversion to the format of the output device. |
| 867 | * @see #KEY_COLOR_RENDERING |
| 868 | */ |
| 869 | public static final Object VALUE_COLOR_RENDER_SPEED = |
| 870 | SunHints.VALUE_COLOR_RENDER_SPEED; |
| 871 | |
| 872 | /** |
| 873 | * Color rendering hint value -- perform the color conversion |
| 874 | * calculations with the highest accuracy and visual quality. |
| 875 | * @see #KEY_COLOR_RENDERING |
| 876 | */ |
| 877 | public static final Object VALUE_COLOR_RENDER_QUALITY = |
| 878 | SunHints.VALUE_COLOR_RENDER_QUALITY; |
| 879 | |
| 880 | /** |
| 881 | * Color rendering hint value -- perform color conversion |
| 882 | * calculations as chosen by the implementation to represent |
| 883 | * the best available tradeoff between performance and |
| 884 | * accuracy. |
| 885 | * @see #KEY_COLOR_RENDERING |
| 886 | */ |
| 887 | public static final Object VALUE_COLOR_RENDER_DEFAULT = |
| 888 | SunHints.VALUE_COLOR_RENDER_DEFAULT; |
| 889 | |
| 890 | /** |
| 891 | * Stroke normalization control hint key. |
| 892 | * The {@code STROKE_CONTROL} hint controls whether a rendering |
| 893 | * implementation should or is allowed to modify the geometry |
| 894 | * of rendered shapes for various purposes. |
| 895 | * <p> |
| 896 | * Some implementations may be able to use an optimized platform |
| 897 | * rendering library which may be faster than traditional software |
| 898 | * rendering algorithms on a given platform, but which may also |
| 899 | * not support floating point coordinates. |
| 900 | * Some implementations may also have sophisticated algorithms |
| 901 | * which perturb the coordinates of a path so that wide lines |
| 902 | * appear more uniform in width and spacing. |
| 903 | * <p> |
| 904 | * If an implementation performs any type of modification or |
| 905 | * "normalization" of a path, it should never move the coordinates |
| 906 | * by more than half a pixel in any direction. |
| 907 | * <p> |
| 908 | * The allowable values for this hint are |
| 909 | * <ul> |
| 910 | * <li>{@link #VALUE_STROKE_NORMALIZE} |
| 911 | * <li>{@link #VALUE_STROKE_PURE} |
| 912 | * <li>{@link #VALUE_STROKE_DEFAULT} |
| 913 | * </ul> |
| 914 | * @since 1.3 |
| 915 | */ |
| 916 | public static final Key KEY_STROKE_CONTROL = |
| 917 | SunHints.KEY_STROKE_CONTROL; |
| 918 | |
| 919 | /** |
| 920 | * Stroke normalization control hint value -- geometry may be |
| 921 | * modified or left pure depending on the tradeoffs in a given |
| 922 | * implementation. |
| 923 | * Typically this setting allows an implementation to use a fast |
| 924 | * integer coordinate based platform rendering library, but does |
| 925 | * not specifically request normalization for uniformity or |
| 926 | * aesthetics. |
| 927 | * |
| 928 | * @see #KEY_STROKE_CONTROL |
| 929 | * @since 1.3 |
| 930 | */ |
| 931 | public static final Object VALUE_STROKE_DEFAULT = |
| 932 | SunHints.VALUE_STROKE_DEFAULT; |
| 933 | |
| 934 | /** |
| 935 | * Stroke normalization control hint value -- geometry should |
| 936 | * be normalized to improve uniformity or spacing of lines and |
| 937 | * overall aesthetics. |
| 938 | * Note that different normalization algorithms may be more |
| 939 | * successful than others for given input paths. |
| 940 | * |
| 941 | * @see #KEY_STROKE_CONTROL |
| 942 | * @since 1.3 |
| 943 | */ |
| 944 | public static final Object VALUE_STROKE_NORMALIZE = |
| 945 | SunHints.VALUE_STROKE_NORMALIZE; |
| 946 | |
| 947 | /** |
| 948 | * Stroke normalization control hint value -- geometry should |
| 949 | * be left unmodified and rendered with sub-pixel accuracy. |
| 950 | * |
| 951 | * @see #KEY_STROKE_CONTROL |
| 952 | * @since 1.3 |
| 953 | */ |
| 954 | public static final Object VALUE_STROKE_PURE = |
| 955 | SunHints.VALUE_STROKE_PURE; |
| 956 | |
| 957 | /** |
| 958 | * Constructs a new object with keys and values initialized |
| 959 | * from the specified Map object which may be null. |
| 960 | * @param init a map of key/value pairs to initialize the hints |
| 961 | * or null if the object should be empty |
| 962 | */ |
| 963 | public RenderingHints(Map<Key,?> init) { |
| 964 | if (init != null) { |
| 965 | hintmap.putAll(init); |
| 966 | } |
| 967 | } |
| 968 | |
| 969 | /** |
| 970 | * Constructs a new object with the specified key/value pair. |
| 971 | * @param key the key of the particular hint property |
| 972 | * @param value the value of the hint property specified with |
| 973 | * <code>key</code> |
| 974 | */ |
| 975 | public RenderingHints(Key key, Object value) { |
| 976 | hintmap.put(key, value); |
| 977 | } |
| 978 | |
| 979 | /** |
| 980 | * Returns the number of key-value mappings in this |
| 981 | * <code>RenderingHints</code>. |
| 982 | * |
| 983 | * @return the number of key-value mappings in this |
| 984 | * <code>RenderingHints</code>. |
| 985 | */ |
| 986 | public int size() { |
| 987 | return hintmap.size(); |
| 988 | } |
| 989 | |
| 990 | /** |
| 991 | * Returns <code>true</code> if this |
| 992 | * <code>RenderingHints</code> contains no key-value mappings. |
| 993 | * |
| 994 | * @return <code>true</code> if this |
| 995 | * <code>RenderingHints</code> contains no key-value mappings. |
| 996 | */ |
| 997 | public boolean isEmpty() { |
| 998 | return hintmap.isEmpty(); |
| 999 | } |
| 1000 | |
| 1001 | /** |
| 1002 | * Returns <code>true</code> if this <code>RenderingHints</code> |
| 1003 | * contains a mapping for the specified key. |
| 1004 | * |
| 1005 | * @param key key whose presence in this |
| 1006 | * <code>RenderingHints</code> is to be tested. |
| 1007 | * @return <code>true</code> if this <code>RenderingHints</code> |
| 1008 | * contains a mapping for the specified key. |
| 1009 | * @exception <code>ClassCastException</code> if the key can not |
| 1010 | * be cast to <code>RenderingHints.Key</code> |
| 1011 | */ |
| 1012 | public boolean containsKey(Object key) { |
| 1013 | return hintmap.containsKey((Key) key); |
| 1014 | } |
| 1015 | |
| 1016 | /** |
| 1017 | * Returns true if this RenderingHints maps one or more keys to the |
| 1018 | * specified value. |
| 1019 | * More formally, returns <code>true</code> if and only |
| 1020 | * if this <code>RenderingHints</code> |
| 1021 | * contains at least one mapping to a value <code>v</code> such that |
| 1022 | * <pre> |
| 1023 | * (value==null ? v==null : value.equals(v)) |
| 1024 | * </pre>. |
| 1025 | * This operation will probably require time linear in the |
| 1026 | * <code>RenderingHints</code> size for most implementations |
| 1027 | * of <code>RenderingHints</code>. |
| 1028 | * |
| 1029 | * @param value value whose presence in this |
| 1030 | * <code>RenderingHints</code> is to be tested. |
| 1031 | * @return <code>true</code> if this <code>RenderingHints</code> |
| 1032 | * maps one or more keys to the specified value. |
| 1033 | */ |
| 1034 | public boolean containsValue(Object value) { |
| 1035 | return hintmap.containsValue(value); |
| 1036 | } |
| 1037 | |
| 1038 | /** |
| 1039 | * Returns the value to which the specified key is mapped. |
| 1040 | * @param key a rendering hint key |
| 1041 | * @return the value to which the key is mapped in this object or |
| 1042 | * <code>null</code> if the key is not mapped to any value in |
| 1043 | * this object. |
| 1044 | * @exception <code>ClassCastException</code> if the key can not |
| 1045 | * be cast to <code>RenderingHints.Key</code> |
| 1046 | * @see #put(Object, Object) |
| 1047 | */ |
| 1048 | public Object get(Object key) { |
| 1049 | return hintmap.get((Key) key); |
| 1050 | } |
| 1051 | |
| 1052 | /** |
| 1053 | * Maps the specified <code>key</code> to the specified |
| 1054 | * <code>value</code> in this <code>RenderingHints</code> object. |
| 1055 | * Neither the key nor the value can be <code>null</code>. |
| 1056 | * The value can be retrieved by calling the <code>get</code> method |
| 1057 | * with a key that is equal to the original key. |
| 1058 | * @param key the rendering hint key. |
| 1059 | * @param value the rendering hint value. |
| 1060 | * @return the previous value of the specified key in this object |
| 1061 | * or <code>null</code> if it did not have one. |
| 1062 | * @exception <code>NullPointerException</code> if the key is |
| 1063 | * <code>null</code>. |
| 1064 | * @exception <code>ClassCastException</code> if the key can not |
| 1065 | * be cast to <code>RenderingHints.Key</code> |
| 1066 | * @exception <code>IllegalArgumentException</code> if the |
| 1067 | * {@link Key#isCompatibleValue(java.lang.Object) |
| 1068 | * Key.isCompatibleValue()} |
| 1069 | * method of the specified key returns false for the |
| 1070 | * specified value |
| 1071 | * @see #get(Object) |
| 1072 | */ |
| 1073 | public Object put(Object key, Object value) { |
| 1074 | if (!((Key) key).isCompatibleValue(value)) { |
| 1075 | throw new IllegalArgumentException(value+ |
| 1076 | " incompatible with "+ |
| 1077 | key); |
| 1078 | } |
| 1079 | return hintmap.put((Key) key, value); |
| 1080 | } |
| 1081 | |
| 1082 | /** |
| 1083 | * Adds all of the keys and corresponding values from the specified |
| 1084 | * <code>RenderingHints</code> object to this |
| 1085 | * <code>RenderingHints</code> object. Keys that are present in |
| 1086 | * this <code>RenderingHints</code> object, but not in the specified |
| 1087 | * <code>RenderingHints</code> object are not affected. |
| 1088 | * @param hints the set of key/value pairs to be added to this |
| 1089 | * <code>RenderingHints</code> object |
| 1090 | */ |
| 1091 | public void add(RenderingHints hints) { |
| 1092 | hintmap.putAll(hints.hintmap); |
| 1093 | } |
| 1094 | |
| 1095 | /** |
| 1096 | * Clears this <code>RenderingHints</code> object of all key/value |
| 1097 | * pairs. |
| 1098 | */ |
| 1099 | public void clear() { |
| 1100 | hintmap.clear(); |
| 1101 | } |
| 1102 | |
| 1103 | /** |
| 1104 | * Removes the key and its corresponding value from this |
| 1105 | * <code>RenderingHints</code> object. This method does nothing if the |
| 1106 | * key is not in this <code>RenderingHints</code> object. |
| 1107 | * @param key the rendering hints key that needs to be removed |
| 1108 | * @exception <code>ClassCastException</code> if the key can not |
| 1109 | * be cast to <code>RenderingHints.Key</code> |
| 1110 | * @return the value to which the key had previously been mapped in this |
| 1111 | * <code>RenderingHints</code> object, or <code>null</code> |
| 1112 | * if the key did not have a mapping. |
| 1113 | */ |
| 1114 | public Object remove(Object key) { |
| 1115 | return hintmap.remove((Key) key); |
| 1116 | } |
| 1117 | |
| 1118 | /** |
| 1119 | * Copies all of the mappings from the specified <code>Map</code> |
| 1120 | * to this <code>RenderingHints</code>. These mappings replace |
| 1121 | * any mappings that this <code>RenderingHints</code> had for any |
| 1122 | * of the keys currently in the specified <code>Map</code>. |
| 1123 | * @param m the specified <code>Map</code> |
| 1124 | * @exception <code>ClassCastException</code> class of a key or value |
| 1125 | * in the specified <code>Map</code> prevents it from being |
| 1126 | * stored in this <code>RenderingHints</code>. |
| 1127 | * @exception <code>IllegalArgumentException</code> some aspect |
| 1128 | * of a key or value in the specified <code>Map</code> |
| 1129 | * prevents it from being stored in |
| 1130 | * this <code>RenderingHints</code>. |
| 1131 | */ |
| 1132 | public void putAll(Map<?,?> m) { |
| 1133 | // ## javac bug? |
| 1134 | //if (m instanceof RenderingHints) { |
| 1135 | if (RenderingHints.class.isInstance(m)) { |
| 1136 | //hintmap.putAll(((RenderingHints) m).hintmap); |
| 1137 | for (Map.Entry<?,?> entry : m.entrySet()) |
| 1138 | hintmap.put(entry.getKey(), entry.getValue()); |
| 1139 | } else { |
| 1140 | // Funnel each key/value pair through our protected put method |
| 1141 | for (Map.Entry<?,?> entry : m.entrySet()) |
| 1142 | put(entry.getKey(), entry.getValue()); |
| 1143 | } |
| 1144 | } |
| 1145 | |
| 1146 | /** |
| 1147 | * Returns a <code>Set</code> view of the Keys contained in this |
| 1148 | * <code>RenderingHints</code>. The Set is backed by the |
| 1149 | * <code>RenderingHints</code>, so changes to the |
| 1150 | * <code>RenderingHints</code> are reflected in the <code>Set</code>, |
| 1151 | * and vice-versa. If the <code>RenderingHints</code> is modified |
| 1152 | * while an iteration over the <code>Set</code> is in progress, |
| 1153 | * the results of the iteration are undefined. The <code>Set</code> |
| 1154 | * supports element removal, which removes the corresponding |
| 1155 | * mapping from the <code>RenderingHints</code>, via the |
| 1156 | * <code>Iterator.remove</code>, <code>Set.remove</code>, |
| 1157 | * <code>removeAll</code> <code>retainAll</code>, and |
| 1158 | * <code>clear</code> operations. It does not support |
| 1159 | * the <code>add</code> or <code>addAll</code> operations. |
| 1160 | * |
| 1161 | * @return a <code>Set</code> view of the keys contained |
| 1162 | * in this <code>RenderingHints</code>. |
| 1163 | */ |
| 1164 | public Set<Object> keySet() { |
| 1165 | return hintmap.keySet(); |
| 1166 | } |
| 1167 | |
| 1168 | /** |
| 1169 | * Returns a <code>Collection</code> view of the values |
| 1170 | * contained in this <code>RenderinHints</code>. |
| 1171 | * The <code>Collection</code> is backed by the |
| 1172 | * <code>RenderingHints</code>, so changes to |
| 1173 | * the <code>RenderingHints</code> are reflected in |
| 1174 | * the <code>Collection</code>, and vice-versa. |
| 1175 | * If the <code>RenderingHints</code> is modified while |
| 1176 | * an iteration over the <code>Collection</code> is |
| 1177 | * in progress, the results of the iteration are undefined. |
| 1178 | * The <code>Collection</code> supports element removal, |
| 1179 | * which removes the corresponding mapping from the |
| 1180 | * <code>RenderingHints</code>, via the |
| 1181 | * <code>Iterator.remove</code>, |
| 1182 | * <code>Collection.remove</code>, <code>removeAll</code>, |
| 1183 | * <code>retainAll</code> and <code>clear</code> operations. |
| 1184 | * It does not support the <code>add</code> or |
| 1185 | * <code>addAll</code> operations. |
| 1186 | * |
| 1187 | * @return a <code>Collection</code> view of the values |
| 1188 | * contained in this <code>RenderingHints</code>. |
| 1189 | */ |
| 1190 | public Collection<Object> values() { |
| 1191 | return hintmap.values(); |
| 1192 | } |
| 1193 | |
| 1194 | /** |
| 1195 | * Returns a <code>Set</code> view of the mappings contained |
| 1196 | * in this <code>RenderingHints</code>. Each element in the |
| 1197 | * returned <code>Set</code> is a <code>Map.Entry</code>. |
| 1198 | * The <code>Set</code> is backed by the <code>RenderingHints</code>, |
| 1199 | * so changes to the <code>RenderingHints</code> are reflected |
| 1200 | * in the <code>Set</code>, and vice-versa. If the |
| 1201 | * <code>RenderingHints</code> is modified while |
| 1202 | * while an iteration over the <code>Set</code> is in progress, |
| 1203 | * the results of the iteration are undefined. |
| 1204 | * <p> |
| 1205 | * The entrySet returned from a <code>RenderingHints</code> object |
| 1206 | * is not modifiable. |
| 1207 | * |
| 1208 | * @return a <code>Set</code> view of the mappings contained in |
| 1209 | * this <code>RenderingHints</code>. |
| 1210 | */ |
| 1211 | public Set<Map.Entry<Object,Object>> entrySet() { |
| 1212 | return Collections.unmodifiableMap(hintmap).entrySet(); |
| 1213 | } |
| 1214 | |
| 1215 | /** |
| 1216 | * Compares the specified <code>Object</code> with this |
| 1217 | * <code>RenderingHints</code> for equality. |
| 1218 | * Returns <code>true</code> if the specified object is also a |
| 1219 | * <code>Map</code> and the two <code>Map</code> objects represent |
| 1220 | * the same mappings. More formally, two <code>Map</code> objects |
| 1221 | * <code>t1</code> and <code>t2</code> represent the same mappings |
| 1222 | * if <code>t1.keySet().equals(t2.keySet())</code> and for every |
| 1223 | * key <code>k</code> in <code>t1.keySet()</code>, |
| 1224 | * <pre> |
| 1225 | * (t1.get(k)==null ? t2.get(k)==null : t1.get(k).equals(t2.get(k))) |
| 1226 | * </pre>. |
| 1227 | * This ensures that the <code>equals</code> method works properly across |
| 1228 | * different implementations of the <code>Map</code> interface. |
| 1229 | * |
| 1230 | * @param o <code>Object</code> to be compared for equality with |
| 1231 | * this <code>RenderingHints</code>. |
| 1232 | * @return <code>true</code> if the specified <code>Object</code> |
| 1233 | * is equal to this <code>RenderingHints</code>. |
| 1234 | */ |
| 1235 | public boolean equals(Object o) { |
| 1236 | if (o instanceof RenderingHints) { |
| 1237 | return hintmap.equals(((RenderingHints) o).hintmap); |
| 1238 | } else if (o instanceof Map) { |
| 1239 | return hintmap.equals(o); |
| 1240 | } |
| 1241 | return false; |
| 1242 | } |
| 1243 | |
| 1244 | /** |
| 1245 | * Returns the hash code value for this <code>RenderingHints</code>. |
| 1246 | * The hash code of a <code>RenderingHints</code> is defined to be |
| 1247 | * the sum of the hashCodes of each <code>Entry</code> in the |
| 1248 | * <code>RenderingHints</code> object's entrySet view. This ensures that |
| 1249 | * <code>t1.equals(t2)</code> implies that |
| 1250 | * <code>t1.hashCode()==t2.hashCode()</code> for any two <code>Map</code> |
| 1251 | * objects <code>t1</code> and <code>t2</code>, as required by the general |
| 1252 | * contract of <code>Object.hashCode</code>. |
| 1253 | * |
| 1254 | * @return the hash code value for this <code>RenderingHints</code>. |
| 1255 | * @see java.util.Map.Entry#hashCode() |
| 1256 | * @see Object#hashCode() |
| 1257 | * @see Object#equals(Object) |
| 1258 | * @see #equals(Object) |
| 1259 | */ |
| 1260 | public int hashCode() { |
| 1261 | return hintmap.hashCode(); |
| 1262 | } |
| 1263 | |
| 1264 | /** |
| 1265 | * Creates a clone of this <code>RenderingHints</code> object |
| 1266 | * that has the same contents as this <code>RenderingHints</code> |
| 1267 | * object. |
| 1268 | * @return a clone of this instance. |
| 1269 | */ |
| 1270 | public Object clone() { |
| 1271 | RenderingHints rh; |
| 1272 | try { |
| 1273 | rh = (RenderingHints) super.clone(); |
| 1274 | if (hintmap != null) { |
| 1275 | rh.hintmap = (HashMap) hintmap.clone(); |
| 1276 | } |
| 1277 | } catch (CloneNotSupportedException e) { |
| 1278 | // this shouldn't happen, since we are Cloneable |
| 1279 | throw new InternalError(); |
| 1280 | } |
| 1281 | |
| 1282 | return rh; |
| 1283 | } |
| 1284 | |
| 1285 | /** |
| 1286 | * Returns a rather long string representation of the hashmap |
| 1287 | * which contains the mappings of keys to values for this |
| 1288 | * <code>RenderingHints</code> object. |
| 1289 | * @return a string representation of this object. |
| 1290 | */ |
| 1291 | public String toString() { |
| 1292 | if (hintmap == null) { |
| 1293 | return getClass().getName() + "@" + |
| 1294 | Integer.toHexString(hashCode()) + |
| 1295 | " (0 hints)"; |
| 1296 | } |
| 1297 | |
| 1298 | return hintmap.toString(); |
| 1299 | } |
| 1300 | } |