J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2004 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.print.attribute; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | import java.io.ObjectInputStream; |
| 30 | import java.io.ObjectOutputStream; |
| 31 | import java.io.Serializable; |
| 32 | import java.util.HashMap; |
| 33 | |
| 34 | /** |
| 35 | * Class HashAttributeSet provides an <code>AttributeSet</code> |
| 36 | * implementation with characteristics of a hash map. |
| 37 | * <P> |
| 38 | * |
| 39 | * @author Alan Kaminsky |
| 40 | */ |
| 41 | public class HashAttributeSet implements AttributeSet, Serializable { |
| 42 | |
| 43 | private static final long serialVersionUID = 5311560590283707917L; |
| 44 | |
| 45 | /** |
| 46 | * The interface of which all members of this attribute set must be an |
| 47 | * instance. It is assumed to be interface {@link Attribute Attribute} |
| 48 | * or a subinterface thereof. |
| 49 | * @serial |
| 50 | */ |
| 51 | private Class myInterface; |
| 52 | |
| 53 | /* |
| 54 | * A HashMap used by the implementation. |
| 55 | * The serialised form doesn't include this instance variable. |
| 56 | */ |
| 57 | private transient HashMap attrMap = new HashMap(); |
| 58 | |
| 59 | /** |
| 60 | * Write the instance to a stream (ie serialize the object) |
| 61 | * |
| 62 | * @serialData |
| 63 | * The serialized form of an attribute set explicitly writes the |
| 64 | * number of attributes in the set, and each of the attributes. |
| 65 | * This does not guarantee equality of serialized forms since |
| 66 | * the order in which the attributes are written is not defined. |
| 67 | */ |
| 68 | private void writeObject(ObjectOutputStream s) throws IOException { |
| 69 | |
| 70 | s.defaultWriteObject(); |
| 71 | Attribute [] attrs = toArray(); |
| 72 | s.writeInt(attrs.length); |
| 73 | for (int i = 0; i < attrs.length; i++) { |
| 74 | s.writeObject(attrs[i]); |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | /** |
| 79 | * Reconstitute an instance from a stream that is, deserialize it). |
| 80 | */ |
| 81 | private void readObject(ObjectInputStream s) |
| 82 | throws ClassNotFoundException, IOException { |
| 83 | |
| 84 | s.defaultReadObject(); |
| 85 | attrMap = new HashMap(); |
| 86 | int count = s.readInt(); |
| 87 | Attribute attr; |
| 88 | for (int i = 0; i < count; i++) { |
| 89 | attr = (Attribute)s.readObject(); |
| 90 | add(attr); |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * Construct a new, empty attribute set. |
| 96 | */ |
| 97 | public HashAttributeSet() { |
| 98 | this(Attribute.class); |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Construct a new attribute set, |
| 103 | * initially populated with the given attribute. |
| 104 | * |
| 105 | * @param attribute Attribute value to add to the set. |
| 106 | * |
| 107 | * @exception NullPointerException |
| 108 | * (unchecked exception) Thrown if <CODE>attribute</CODE> is null. |
| 109 | */ |
| 110 | public HashAttributeSet(Attribute attribute) { |
| 111 | this (attribute, Attribute.class); |
| 112 | } |
| 113 | |
| 114 | /** |
| 115 | * Construct a new attribute set, |
| 116 | * initially populated with the values from the |
| 117 | * given array. The new attribute set is populated by |
| 118 | * adding the elements of <CODE>attributes</CODE> array to the set in |
| 119 | * sequence, starting at index 0. Thus, later array elements may replace |
| 120 | * earlier array elements if the array contains duplicate attribute |
| 121 | * values or attribute categories. |
| 122 | * |
| 123 | * @param attributes Array of attribute values to add to the set. |
| 124 | * If null, an empty attribute set is constructed. |
| 125 | * |
| 126 | * @exception NullPointerException |
| 127 | * (unchecked exception) Thrown if any element of |
| 128 | * <CODE>attributes</CODE> is null. |
| 129 | */ |
| 130 | public HashAttributeSet(Attribute[] attributes) { |
| 131 | this (attributes, Attribute.class); |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * Construct a new attribute set, |
| 136 | * initially populated with the values from the given set. |
| 137 | * |
| 138 | * @param attributes Set of attributes from which to initialise this set. |
| 139 | * If null, an empty attribute set is constructed. |
| 140 | * |
| 141 | */ |
| 142 | public HashAttributeSet(AttributeSet attributes) { |
| 143 | this (attributes, Attribute.class); |
| 144 | } |
| 145 | |
| 146 | /** |
| 147 | * Construct a new, empty attribute set, where the members of |
| 148 | * the attribute set are restricted to the given interface. |
| 149 | * |
| 150 | * @param interfaceName The interface of which all members of this |
| 151 | * attribute set must be an instance. It is assumed to |
| 152 | * be interface {@link Attribute Attribute} or a |
| 153 | * subinterface thereof. |
| 154 | * @exception NullPointerException if interfaceName is null. |
| 155 | */ |
| 156 | protected HashAttributeSet(Class<?> interfaceName) { |
| 157 | if (interfaceName == null) { |
| 158 | throw new NullPointerException("null interface"); |
| 159 | } |
| 160 | myInterface = interfaceName; |
| 161 | } |
| 162 | |
| 163 | /** |
| 164 | * Construct a new attribute set, initially populated with the given |
| 165 | * attribute, where the members of the attribute set are restricted to the |
| 166 | * given interface. |
| 167 | * |
| 168 | * @param attribute Attribute value to add to the set. |
| 169 | * @param interfaceName The interface of which all members of this |
| 170 | * attribute set must be an instance. It is assumed to |
| 171 | * be interface {@link Attribute Attribute} or a |
| 172 | * subinterface thereof. |
| 173 | * |
| 174 | * @exception NullPointerException |
| 175 | * (unchecked exception) Thrown if <CODE>attribute</CODE> is null. |
| 176 | * @exception NullPointerException if interfaceName is null. |
| 177 | * @exception ClassCastException |
| 178 | * (unchecked exception) Thrown if <CODE>attribute</CODE> is not an |
| 179 | * instance of <CODE>interfaceName</CODE>. |
| 180 | */ |
| 181 | protected HashAttributeSet(Attribute attribute, Class<?> interfaceName) { |
| 182 | if (interfaceName == null) { |
| 183 | throw new NullPointerException("null interface"); |
| 184 | } |
| 185 | myInterface = interfaceName; |
| 186 | add (attribute); |
| 187 | } |
| 188 | |
| 189 | /** |
| 190 | * Construct a new attribute set, where the members of the attribute |
| 191 | * set are restricted to the given interface. |
| 192 | * The new attribute set is populated |
| 193 | * by adding the elements of <CODE>attributes</CODE> array to the set in |
| 194 | * sequence, starting at index 0. Thus, later array elements may replace |
| 195 | * earlier array elements if the array contains duplicate attribute |
| 196 | * values or attribute categories. |
| 197 | * |
| 198 | * @param attributes Array of attribute values to add to the set. If |
| 199 | * null, an empty attribute set is constructed. |
| 200 | * @param interfaceName The interface of which all members of this |
| 201 | * attribute set must be an instance. It is assumed to |
| 202 | * be interface {@link Attribute Attribute} or a |
| 203 | * subinterface thereof. |
| 204 | * |
| 205 | * @exception NullPointerException |
| 206 | * (unchecked exception) Thrown if any element of |
| 207 | * <CODE>attributes</CODE> is null. |
| 208 | * @exception NullPointerException if interfaceName is null. |
| 209 | * @exception ClassCastException |
| 210 | * (unchecked exception) Thrown if any element of |
| 211 | * <CODE>attributes</CODE> is not an instance of |
| 212 | * <CODE>interfaceName</CODE>. |
| 213 | */ |
| 214 | protected HashAttributeSet(Attribute[] attributes, Class<?> interfaceName) { |
| 215 | if (interfaceName == null) { |
| 216 | throw new NullPointerException("null interface"); |
| 217 | } |
| 218 | myInterface = interfaceName; |
| 219 | int n = attributes == null ? 0 : attributes.length; |
| 220 | for (int i = 0; i < n; ++ i) { |
| 221 | add (attributes[i]); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * Construct a new attribute set, initially populated with the |
| 227 | * values from the given set where the members of the attribute |
| 228 | * set are restricted to the given interface. |
| 229 | * |
| 230 | * @param attributes set of attribute values to initialise the set. If |
| 231 | * null, an empty attribute set is constructed. |
| 232 | * @param interfaceName The interface of which all members of this |
| 233 | * attribute set must be an instance. It is assumed to |
| 234 | * be interface {@link Attribute Attribute} or a |
| 235 | * subinterface thereof. |
| 236 | * |
| 237 | * @exception ClassCastException |
| 238 | * (unchecked exception) Thrown if any element of |
| 239 | * <CODE>attributes</CODE> is not an instance of |
| 240 | * <CODE>interfaceName</CODE>. |
| 241 | */ |
| 242 | protected HashAttributeSet(AttributeSet attributes, Class<?> interfaceName) { |
| 243 | myInterface = interfaceName; |
| 244 | if (attributes != null) { |
| 245 | Attribute[] attribArray = attributes.toArray(); |
| 246 | int n = attribArray == null ? 0 : attribArray.length; |
| 247 | for (int i = 0; i < n; ++ i) { |
| 248 | add (attribArray[i]); |
| 249 | } |
| 250 | } |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * Returns the attribute value which this attribute set contains in the |
| 255 | * given attribute category. Returns <tt>null</tt> if this attribute set |
| 256 | * does not contain any attribute value in the given attribute category. |
| 257 | * |
| 258 | * @param category Attribute category whose associated attribute value |
| 259 | * is to be returned. It must be a |
| 260 | * {@link java.lang.Class Class} |
| 261 | * that implements interface {@link Attribute |
| 262 | * Attribute}. |
| 263 | * |
| 264 | * @return The attribute value in the given attribute category contained |
| 265 | * in this attribute set, or <tt>null</tt> if this attribute set |
| 266 | * does not contain any attribute value in the given attribute |
| 267 | * category. |
| 268 | * |
| 269 | * @throws NullPointerException |
| 270 | * (unchecked exception) Thrown if the <CODE>category</CODE> is null. |
| 271 | * @throws ClassCastException |
| 272 | * (unchecked exception) Thrown if the <CODE>category</CODE> is not a |
| 273 | * {@link java.lang.Class Class} that implements interface {@link |
| 274 | * Attribute Attribute}. |
| 275 | */ |
| 276 | public Attribute get(Class<?> category) { |
| 277 | return (Attribute) |
| 278 | attrMap.get(AttributeSetUtilities. |
| 279 | verifyAttributeCategory(category, |
| 280 | Attribute.class)); |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * Adds the specified attribute to this attribute set if it is not |
| 285 | * already present, first removing any existing in the same |
| 286 | * attribute category as the specified attribute value. |
| 287 | * |
| 288 | * @param attribute Attribute value to be added to this attribute set. |
| 289 | * |
| 290 | * @return <tt>true</tt> if this attribute set changed as a result of the |
| 291 | * call, i.e., the given attribute value was not already a |
| 292 | * member of this attribute set. |
| 293 | * |
| 294 | * @throws NullPointerException |
| 295 | * (unchecked exception) Thrown if the <CODE>attribute</CODE> is null. |
| 296 | * @throws UnmodifiableSetException |
| 297 | * (unchecked exception) Thrown if this attribute set does not support |
| 298 | * the <CODE>add()</CODE> operation. |
| 299 | */ |
| 300 | public boolean add(Attribute attribute) { |
| 301 | Object oldAttribute = |
| 302 | attrMap.put(attribute.getCategory(), |
| 303 | AttributeSetUtilities. |
| 304 | verifyAttributeValue(attribute, myInterface)); |
| 305 | return (!attribute.equals(oldAttribute)); |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * Removes any attribute for this category from this attribute set if |
| 310 | * present. If <CODE>category</CODE> is null, then |
| 311 | * <CODE>remove()</CODE> does nothing and returns <tt>false</tt>. |
| 312 | * |
| 313 | * @param category Attribute category to be removed from this |
| 314 | * attribute set. |
| 315 | * |
| 316 | * @return <tt>true</tt> if this attribute set changed as a result of the |
| 317 | * call, i.e., the given attribute category had been a member of |
| 318 | * this attribute set. |
| 319 | * |
| 320 | * @throws UnmodifiableSetException |
| 321 | * (unchecked exception) Thrown if this attribute set does not |
| 322 | * support the <CODE>remove()</CODE> operation. |
| 323 | */ |
| 324 | public boolean remove(Class<?> category) { |
| 325 | return |
| 326 | category != null && |
| 327 | AttributeSetUtilities. |
| 328 | verifyAttributeCategory(category, Attribute.class) != null && |
| 329 | attrMap.remove(category) != null; |
| 330 | } |
| 331 | |
| 332 | /** |
| 333 | * Removes the specified attribute from this attribute set if |
| 334 | * present. If <CODE>attribute</CODE> is null, then |
| 335 | * <CODE>remove()</CODE> does nothing and returns <tt>false</tt>. |
| 336 | * |
| 337 | * @param attribute Attribute value to be removed from this attribute set. |
| 338 | * |
| 339 | * @return <tt>true</tt> if this attribute set changed as a result of the |
| 340 | * call, i.e., the given attribute value had been a member of |
| 341 | * this attribute set. |
| 342 | * |
| 343 | * @throws UnmodifiableSetException |
| 344 | * (unchecked exception) Thrown if this attribute set does not |
| 345 | * support the <CODE>remove()</CODE> operation. |
| 346 | */ |
| 347 | public boolean remove(Attribute attribute) { |
| 348 | return |
| 349 | attribute != null && |
| 350 | attrMap.remove(attribute.getCategory()) != null; |
| 351 | } |
| 352 | |
| 353 | /** |
| 354 | * Returns <tt>true</tt> if this attribute set contains an |
| 355 | * attribute for the specified category. |
| 356 | * |
| 357 | * @param category whose presence in this attribute set is |
| 358 | * to be tested. |
| 359 | * |
| 360 | * @return <tt>true</tt> if this attribute set contains an attribute |
| 361 | * value for the specified category. |
| 362 | */ |
| 363 | public boolean containsKey(Class<?> category) { |
| 364 | return |
| 365 | category != null && |
| 366 | AttributeSetUtilities. |
| 367 | verifyAttributeCategory(category, Attribute.class) != null && |
| 368 | attrMap.get(category) != null; |
| 369 | } |
| 370 | |
| 371 | /** |
| 372 | * Returns <tt>true</tt> if this attribute set contains the given |
| 373 | * attribute. |
| 374 | * |
| 375 | * @param attribute value whose presence in this attribute set is |
| 376 | * to be tested. |
| 377 | * |
| 378 | * @return <tt>true</tt> if this attribute set contains the given |
| 379 | * attribute value. |
| 380 | */ |
| 381 | public boolean containsValue(Attribute attribute) { |
| 382 | return |
| 383 | attribute != null && |
| 384 | attribute instanceof Attribute && |
| 385 | attribute.equals(attrMap.get(((Attribute)attribute).getCategory())); |
| 386 | } |
| 387 | |
| 388 | /** |
| 389 | * Adds all of the elements in the specified set to this attribute. |
| 390 | * The outcome is the same as if the |
| 391 | * {@link #add(Attribute) <CODE>add(Attribute)</CODE>} |
| 392 | * operation had been applied to this attribute set successively with |
| 393 | * each element from the specified set. |
| 394 | * The behavior of the <CODE>addAll(AttributeSet)</CODE> |
| 395 | * operation is unspecified if the specified set is modified while |
| 396 | * the operation is in progress. |
| 397 | * <P> |
| 398 | * If the <CODE>addAll(AttributeSet)</CODE> operation throws an exception, |
| 399 | * the effect on this attribute set's state is implementation dependent; |
| 400 | * elements from the specified set before the point of the exception may |
| 401 | * or may not have been added to this attribute set. |
| 402 | * |
| 403 | * @param attributes whose elements are to be added to this attribute |
| 404 | * set. |
| 405 | * |
| 406 | * @return <tt>true</tt> if this attribute set changed as a result of the |
| 407 | * call. |
| 408 | * |
| 409 | * @throws UnmodifiableSetException |
| 410 | * (Unchecked exception) Thrown if this attribute set does not |
| 411 | * support the <tt>addAll(AttributeSet)</tt> method. |
| 412 | * @throws NullPointerException |
| 413 | * (Unchecked exception) Thrown if some element in the specified |
| 414 | * set is null, or the set is null. |
| 415 | * |
| 416 | * @see #add(Attribute) |
| 417 | */ |
| 418 | public boolean addAll(AttributeSet attributes) { |
| 419 | |
| 420 | Attribute []attrs = attributes.toArray(); |
| 421 | boolean result = false; |
| 422 | for (int i=0; i<attrs.length; i++) { |
| 423 | Attribute newValue = |
| 424 | AttributeSetUtilities.verifyAttributeValue(attrs[i], |
| 425 | myInterface); |
| 426 | Object oldValue = attrMap.put(newValue.getCategory(), newValue); |
| 427 | result = (! newValue.equals(oldValue)) || result; |
| 428 | } |
| 429 | return result; |
| 430 | } |
| 431 | |
| 432 | /** |
| 433 | * Returns the number of attributes in this attribute set. If this |
| 434 | * attribute set contains more than <tt>Integer.MAX_VALUE</tt> elements, |
| 435 | * returns <tt>Integer.MAX_VALUE</tt>. |
| 436 | * |
| 437 | * @return The number of attributes in this attribute set. |
| 438 | */ |
| 439 | public int size() { |
| 440 | return attrMap.size(); |
| 441 | } |
| 442 | |
| 443 | /** |
| 444 | * |
| 445 | * @return the Attributes contained in this set as an array, zero length |
| 446 | * if the AttributeSet is empty. |
| 447 | */ |
| 448 | public Attribute[] toArray() { |
| 449 | Attribute []attrs = new Attribute[size()]; |
| 450 | attrMap.values().toArray(attrs); |
| 451 | return attrs; |
| 452 | } |
| 453 | |
| 454 | |
| 455 | /** |
| 456 | * Removes all attributes from this attribute set. |
| 457 | * |
| 458 | * @throws UnmodifiableSetException |
| 459 | * (unchecked exception) Thrown if this attribute set does not support |
| 460 | * the <CODE>clear()</CODE> operation. |
| 461 | */ |
| 462 | public void clear() { |
| 463 | attrMap.clear(); |
| 464 | } |
| 465 | |
| 466 | /** |
| 467 | * Returns true if this attribute set contains no attributes. |
| 468 | * |
| 469 | * @return true if this attribute set contains no attributes. |
| 470 | */ |
| 471 | public boolean isEmpty() { |
| 472 | return attrMap.isEmpty(); |
| 473 | } |
| 474 | |
| 475 | /** |
| 476 | * Compares the specified object with this attribute set for equality. |
| 477 | * Returns <tt>true</tt> if the given object is also an attribute set and |
| 478 | * the two attribute sets contain the same attribute category-attribute |
| 479 | * value mappings. This ensures that the |
| 480 | * <tt>equals()</tt> method works properly across different |
| 481 | * implementations of the AttributeSet interface. |
| 482 | * |
| 483 | * @param object to be compared for equality with this attribute set. |
| 484 | * |
| 485 | * @return <tt>true</tt> if the specified object is equal to this |
| 486 | * attribute set. |
| 487 | */ |
| 488 | |
| 489 | public boolean equals(Object object) { |
| 490 | if (object == null || !(object instanceof AttributeSet)) { |
| 491 | return false; |
| 492 | } |
| 493 | |
| 494 | AttributeSet aset = (AttributeSet)object; |
| 495 | if (aset.size() != size()) { |
| 496 | return false; |
| 497 | } |
| 498 | |
| 499 | Attribute[] attrs = toArray(); |
| 500 | for (int i=0;i<attrs.length; i++) { |
| 501 | if (!aset.containsValue(attrs[i])) { |
| 502 | return false; |
| 503 | } |
| 504 | } |
| 505 | return true; |
| 506 | } |
| 507 | |
| 508 | /** |
| 509 | * Returns the hash code value for this attribute set. |
| 510 | * The hash code of an attribute set is defined to be the sum |
| 511 | * of the hash codes of each entry in the AttributeSet. |
| 512 | * This ensures that <tt>t1.equals(t2)</tt> implies that |
| 513 | * <tt>t1.hashCode()==t2.hashCode()</tt> for any two attribute sets |
| 514 | * <tt>t1</tt> and <tt>t2</tt>, as required by the general contract of |
| 515 | * {@link java.lang.Object#hashCode() <CODE>Object.hashCode()</CODE>}. |
| 516 | * |
| 517 | * @return The hash code value for this attribute set. |
| 518 | */ |
| 519 | public int hashCode() { |
| 520 | int hcode = 0; |
| 521 | Attribute[] attrs = toArray(); |
| 522 | for (int i=0;i<attrs.length; i++) { |
| 523 | hcode += attrs[i].hashCode(); |
| 524 | } |
| 525 | return hcode; |
| 526 | } |
| 527 | |
| 528 | } |