J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1996-2006 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.lang.reflect; |
| 27 | |
| 28 | /** |
| 29 | * The {@code Array} class provides static methods to dynamically create and |
| 30 | * access Java arrays. |
| 31 | * |
| 32 | * <p>{@code Array} permits widening conversions to occur during a get or set |
| 33 | * operation, but throws an {@code IllegalArgumentException} if a narrowing |
| 34 | * conversion would occur. |
| 35 | * |
| 36 | * @author Nakul Saraiya |
| 37 | */ |
| 38 | public final |
| 39 | class Array { |
| 40 | |
| 41 | /** |
| 42 | * Constructor. Class Array is not instantiable. |
| 43 | */ |
| 44 | private Array() {} |
| 45 | |
| 46 | /** |
| 47 | * Creates a new array with the specified component type and |
| 48 | * length. |
| 49 | * Invoking this method is equivalent to creating an array |
| 50 | * as follows: |
| 51 | * <blockquote> |
| 52 | * <pre> |
| 53 | * int[] x = {length}; |
| 54 | * Array.newInstance(componentType, x); |
| 55 | * </pre> |
| 56 | * </blockquote> |
| 57 | * |
| 58 | * @param componentType the {@code Class} object representing the |
| 59 | * component type of the new array |
| 60 | * @param length the length of the new array |
| 61 | * @return the new array |
| 62 | * @exception NullPointerException if the specified |
| 63 | * {@code componentType} parameter is null |
| 64 | * @exception IllegalArgumentException if componentType is {@link Void#TYPE} |
| 65 | * @exception NegativeArraySizeException if the specified {@code length} |
| 66 | * is negative |
| 67 | */ |
| 68 | public static Object newInstance(Class<?> componentType, int length) |
| 69 | throws NegativeArraySizeException { |
| 70 | return newArray(componentType, length); |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Creates a new array |
| 75 | * with the specified component type and dimensions. |
| 76 | * If {@code componentType} |
| 77 | * represents a non-array class or interface, the new array |
| 78 | * has {@code dimensions.length} dimensions and |
| 79 | * {@code componentType} as its component type. If |
| 80 | * {@code componentType} represents an array class, the |
| 81 | * number of dimensions of the new array is equal to the sum |
| 82 | * of {@code dimensions.length} and the number of |
| 83 | * dimensions of {@code componentType}. In this case, the |
| 84 | * component type of the new array is the component type of |
| 85 | * {@code componentType}. |
| 86 | * |
| 87 | * <p>The number of dimensions of the new array must not |
| 88 | * exceed the number of array dimensions supported by the |
| 89 | * implementation (typically 255). |
| 90 | * |
| 91 | * @param componentType the {@code Class} object representing the component |
| 92 | * type of the new array |
| 93 | * @param dimensions an array of {@code int} representing the dimensions of |
| 94 | * the new array |
| 95 | * @return the new array |
| 96 | * @exception NullPointerException if the specified |
| 97 | * {@code componentType} argument is null |
| 98 | * @exception IllegalArgumentException if the specified {@code dimensions} |
| 99 | * argument is a zero-dimensional array, or if the number of |
| 100 | * requested dimensions exceeds the limit on the number of array dimensions |
| 101 | * supported by the implementation (typically 255), or if componentType |
| 102 | * is {@link Void#TYPE}. |
| 103 | * @exception NegativeArraySizeException if any of the components in |
| 104 | * the specified {@code dimensions} argument is negative. |
| 105 | */ |
| 106 | public static Object newInstance(Class<?> componentType, int... dimensions) |
| 107 | throws IllegalArgumentException, NegativeArraySizeException { |
| 108 | return multiNewArray(componentType, dimensions); |
| 109 | } |
| 110 | |
| 111 | /** |
| 112 | * Returns the length of the specified array object, as an {@code int}. |
| 113 | * |
| 114 | * @param array the array |
| 115 | * @return the length of the array |
| 116 | * @exception IllegalArgumentException if the object argument is not |
| 117 | * an array |
| 118 | */ |
| 119 | public static native int getLength(Object array) |
| 120 | throws IllegalArgumentException; |
| 121 | |
| 122 | /** |
| 123 | * Returns the value of the indexed component in the specified |
| 124 | * array object. The value is automatically wrapped in an object |
| 125 | * if it has a primitive type. |
| 126 | * |
| 127 | * @param array the array |
| 128 | * @param index the index |
| 129 | * @return the (possibly wrapped) value of the indexed component in |
| 130 | * the specified array |
| 131 | * @exception NullPointerException If the specified object is null |
| 132 | * @exception IllegalArgumentException If the specified object is not |
| 133 | * an array |
| 134 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 135 | * argument is negative, or if it is greater than or equal to the |
| 136 | * length of the specified array |
| 137 | */ |
| 138 | public static native Object get(Object array, int index) |
| 139 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 140 | |
| 141 | /** |
| 142 | * Returns the value of the indexed component in the specified |
| 143 | * array object, as a {@code boolean}. |
| 144 | * |
| 145 | * @param array the array |
| 146 | * @param index the index |
| 147 | * @return the value of the indexed component in the specified array |
| 148 | * @exception NullPointerException If the specified object is null |
| 149 | * @exception IllegalArgumentException If the specified object is not |
| 150 | * an array, or if the indexed element cannot be converted to the |
| 151 | * return type by an identity or widening conversion |
| 152 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 153 | * argument is negative, or if it is greater than or equal to the |
| 154 | * length of the specified array |
| 155 | * @see Array#get |
| 156 | */ |
| 157 | public static native boolean getBoolean(Object array, int index) |
| 158 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 159 | |
| 160 | /** |
| 161 | * Returns the value of the indexed component in the specified |
| 162 | * array object, as a {@code byte}. |
| 163 | * |
| 164 | * @param array the array |
| 165 | * @param index the index |
| 166 | * @return the value of the indexed component in the specified array |
| 167 | * @exception NullPointerException If the specified object is null |
| 168 | * @exception IllegalArgumentException If the specified object is not |
| 169 | * an array, or if the indexed element cannot be converted to the |
| 170 | * return type by an identity or widening conversion |
| 171 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 172 | * argument is negative, or if it is greater than or equal to the |
| 173 | * length of the specified array |
| 174 | * @see Array#get |
| 175 | */ |
| 176 | public static native byte getByte(Object array, int index) |
| 177 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 178 | |
| 179 | /** |
| 180 | * Returns the value of the indexed component in the specified |
| 181 | * array object, as a {@code char}. |
| 182 | * |
| 183 | * @param array the array |
| 184 | * @param index the index |
| 185 | * @return the value of the indexed component in the specified array |
| 186 | * @exception NullPointerException If the specified object is null |
| 187 | * @exception IllegalArgumentException If the specified object is not |
| 188 | * an array, or if the indexed element cannot be converted to the |
| 189 | * return type by an identity or widening conversion |
| 190 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 191 | * argument is negative, or if it is greater than or equal to the |
| 192 | * length of the specified array |
| 193 | * @see Array#get |
| 194 | */ |
| 195 | public static native char getChar(Object array, int index) |
| 196 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 197 | |
| 198 | /** |
| 199 | * Returns the value of the indexed component in the specified |
| 200 | * array object, as a {@code short}. |
| 201 | * |
| 202 | * @param array the array |
| 203 | * @param index the index |
| 204 | * @return the value of the indexed component in the specified array |
| 205 | * @exception NullPointerException If the specified object is null |
| 206 | * @exception IllegalArgumentException If the specified object is not |
| 207 | * an array, or if the indexed element cannot be converted to the |
| 208 | * return type by an identity or widening conversion |
| 209 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 210 | * argument is negative, or if it is greater than or equal to the |
| 211 | * length of the specified array |
| 212 | * @see Array#get |
| 213 | */ |
| 214 | public static native short getShort(Object array, int index) |
| 215 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 216 | |
| 217 | /** |
| 218 | * Returns the value of the indexed component in the specified |
| 219 | * array object, as an {@code int}. |
| 220 | * |
| 221 | * @param array the array |
| 222 | * @param index the index |
| 223 | * @return the value of the indexed component in the specified array |
| 224 | * @exception NullPointerException If the specified object is null |
| 225 | * @exception IllegalArgumentException If the specified object is not |
| 226 | * an array, or if the indexed element cannot be converted to the |
| 227 | * return type by an identity or widening conversion |
| 228 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 229 | * argument is negative, or if it is greater than or equal to the |
| 230 | * length of the specified array |
| 231 | * @see Array#get |
| 232 | */ |
| 233 | public static native int getInt(Object array, int index) |
| 234 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 235 | |
| 236 | /** |
| 237 | * Returns the value of the indexed component in the specified |
| 238 | * array object, as a {@code long}. |
| 239 | * |
| 240 | * @param array the array |
| 241 | * @param index the index |
| 242 | * @return the value of the indexed component in the specified array |
| 243 | * @exception NullPointerException If the specified object is null |
| 244 | * @exception IllegalArgumentException If the specified object is not |
| 245 | * an array, or if the indexed element cannot be converted to the |
| 246 | * return type by an identity or widening conversion |
| 247 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 248 | * argument is negative, or if it is greater than or equal to the |
| 249 | * length of the specified array |
| 250 | * @see Array#get |
| 251 | */ |
| 252 | public static native long getLong(Object array, int index) |
| 253 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 254 | |
| 255 | /** |
| 256 | * Returns the value of the indexed component in the specified |
| 257 | * array object, as a {@code float}. |
| 258 | * |
| 259 | * @param array the array |
| 260 | * @param index the index |
| 261 | * @return the value of the indexed component in the specified array |
| 262 | * @exception NullPointerException If the specified object is null |
| 263 | * @exception IllegalArgumentException If the specified object is not |
| 264 | * an array, or if the indexed element cannot be converted to the |
| 265 | * return type by an identity or widening conversion |
| 266 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 267 | * argument is negative, or if it is greater than or equal to the |
| 268 | * length of the specified array |
| 269 | * @see Array#get |
| 270 | */ |
| 271 | public static native float getFloat(Object array, int index) |
| 272 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 273 | |
| 274 | /** |
| 275 | * Returns the value of the indexed component in the specified |
| 276 | * array object, as a {@code double}. |
| 277 | * |
| 278 | * @param array the array |
| 279 | * @param index the index |
| 280 | * @return the value of the indexed component in the specified array |
| 281 | * @exception NullPointerException If the specified object is null |
| 282 | * @exception IllegalArgumentException If the specified object is not |
| 283 | * an array, or if the indexed element cannot be converted to the |
| 284 | * return type by an identity or widening conversion |
| 285 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 286 | * argument is negative, or if it is greater than or equal to the |
| 287 | * length of the specified array |
| 288 | * @see Array#get |
| 289 | */ |
| 290 | public static native double getDouble(Object array, int index) |
| 291 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 292 | |
| 293 | /** |
| 294 | * Sets the value of the indexed component of the specified array |
| 295 | * object to the specified new value. The new value is first |
| 296 | * automatically unwrapped if the array has a primitive component |
| 297 | * type. |
| 298 | * @param array the array |
| 299 | * @param index the index into the array |
| 300 | * @param value the new value of the indexed component |
| 301 | * @exception NullPointerException If the specified object argument |
| 302 | * is null |
| 303 | * @exception IllegalArgumentException If the specified object argument |
| 304 | * is not an array, or if the array component type is primitive and |
| 305 | * an unwrapping conversion fails |
| 306 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 307 | * argument is negative, or if it is greater than or equal to |
| 308 | * the length of the specified array |
| 309 | */ |
| 310 | public static native void set(Object array, int index, Object value) |
| 311 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 312 | |
| 313 | /** |
| 314 | * Sets the value of the indexed component of the specified array |
| 315 | * object to the specified {@code boolean} value. |
| 316 | * @param array the array |
| 317 | * @param index the index into the array |
| 318 | * @param z the new value of the indexed component |
| 319 | * @exception NullPointerException If the specified object argument |
| 320 | * is null |
| 321 | * @exception IllegalArgumentException If the specified object argument |
| 322 | * is not an array, or if the specified value cannot be converted |
| 323 | * to the underlying array's component type by an identity or a |
| 324 | * primitive widening conversion |
| 325 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 326 | * argument is negative, or if it is greater than or equal to |
| 327 | * the length of the specified array |
| 328 | * @see Array#set |
| 329 | */ |
| 330 | public static native void setBoolean(Object array, int index, boolean z) |
| 331 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 332 | |
| 333 | /** |
| 334 | * Sets the value of the indexed component of the specified array |
| 335 | * object to the specified {@code byte} value. |
| 336 | * @param array the array |
| 337 | * @param index the index into the array |
| 338 | * @param b the new value of the indexed component |
| 339 | * @exception NullPointerException If the specified object argument |
| 340 | * is null |
| 341 | * @exception IllegalArgumentException If the specified object argument |
| 342 | * is not an array, or if the specified value cannot be converted |
| 343 | * to the underlying array's component type by an identity or a |
| 344 | * primitive widening conversion |
| 345 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 346 | * argument is negative, or if it is greater than or equal to |
| 347 | * the length of the specified array |
| 348 | * @see Array#set |
| 349 | */ |
| 350 | public static native void setByte(Object array, int index, byte b) |
| 351 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 352 | |
| 353 | /** |
| 354 | * Sets the value of the indexed component of the specified array |
| 355 | * object to the specified {@code char} value. |
| 356 | * @param array the array |
| 357 | * @param index the index into the array |
| 358 | * @param c the new value of the indexed component |
| 359 | * @exception NullPointerException If the specified object argument |
| 360 | * is null |
| 361 | * @exception IllegalArgumentException If the specified object argument |
| 362 | * is not an array, or if the specified value cannot be converted |
| 363 | * to the underlying array's component type by an identity or a |
| 364 | * primitive widening conversion |
| 365 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 366 | * argument is negative, or if it is greater than or equal to |
| 367 | * the length of the specified array |
| 368 | * @see Array#set |
| 369 | */ |
| 370 | public static native void setChar(Object array, int index, char c) |
| 371 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 372 | |
| 373 | /** |
| 374 | * Sets the value of the indexed component of the specified array |
| 375 | * object to the specified {@code short} value. |
| 376 | * @param array the array |
| 377 | * @param index the index into the array |
| 378 | * @param s the new value of the indexed component |
| 379 | * @exception NullPointerException If the specified object argument |
| 380 | * is null |
| 381 | * @exception IllegalArgumentException If the specified object argument |
| 382 | * is not an array, or if the specified value cannot be converted |
| 383 | * to the underlying array's component type by an identity or a |
| 384 | * primitive widening conversion |
| 385 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 386 | * argument is negative, or if it is greater than or equal to |
| 387 | * the length of the specified array |
| 388 | * @see Array#set |
| 389 | */ |
| 390 | public static native void setShort(Object array, int index, short s) |
| 391 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 392 | |
| 393 | /** |
| 394 | * Sets the value of the indexed component of the specified array |
| 395 | * object to the specified {@code int} value. |
| 396 | * @param array the array |
| 397 | * @param index the index into the array |
| 398 | * @param i the new value of the indexed component |
| 399 | * @exception NullPointerException If the specified object argument |
| 400 | * is null |
| 401 | * @exception IllegalArgumentException If the specified object argument |
| 402 | * is not an array, or if the specified value cannot be converted |
| 403 | * to the underlying array's component type by an identity or a |
| 404 | * primitive widening conversion |
| 405 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 406 | * argument is negative, or if it is greater than or equal to |
| 407 | * the length of the specified array |
| 408 | * @see Array#set |
| 409 | */ |
| 410 | public static native void setInt(Object array, int index, int i) |
| 411 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 412 | |
| 413 | /** |
| 414 | * Sets the value of the indexed component of the specified array |
| 415 | * object to the specified {@code long} value. |
| 416 | * @param array the array |
| 417 | * @param index the index into the array |
| 418 | * @param l the new value of the indexed component |
| 419 | * @exception NullPointerException If the specified object argument |
| 420 | * is null |
| 421 | * @exception IllegalArgumentException If the specified object argument |
| 422 | * is not an array, or if the specified value cannot be converted |
| 423 | * to the underlying array's component type by an identity or a |
| 424 | * primitive widening conversion |
| 425 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 426 | * argument is negative, or if it is greater than or equal to |
| 427 | * the length of the specified array |
| 428 | * @see Array#set |
| 429 | */ |
| 430 | public static native void setLong(Object array, int index, long l) |
| 431 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 432 | |
| 433 | /** |
| 434 | * Sets the value of the indexed component of the specified array |
| 435 | * object to the specified {@code float} value. |
| 436 | * @param array the array |
| 437 | * @param index the index into the array |
| 438 | * @param f the new value of the indexed component |
| 439 | * @exception NullPointerException If the specified object argument |
| 440 | * is null |
| 441 | * @exception IllegalArgumentException If the specified object argument |
| 442 | * is not an array, or if the specified value cannot be converted |
| 443 | * to the underlying array's component type by an identity or a |
| 444 | * primitive widening conversion |
| 445 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 446 | * argument is negative, or if it is greater than or equal to |
| 447 | * the length of the specified array |
| 448 | * @see Array#set |
| 449 | */ |
| 450 | public static native void setFloat(Object array, int index, float f) |
| 451 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 452 | |
| 453 | /** |
| 454 | * Sets the value of the indexed component of the specified array |
| 455 | * object to the specified {@code double} value. |
| 456 | * @param array the array |
| 457 | * @param index the index into the array |
| 458 | * @param d the new value of the indexed component |
| 459 | * @exception NullPointerException If the specified object argument |
| 460 | * is null |
| 461 | * @exception IllegalArgumentException If the specified object argument |
| 462 | * is not an array, or if the specified value cannot be converted |
| 463 | * to the underlying array's component type by an identity or a |
| 464 | * primitive widening conversion |
| 465 | * @exception ArrayIndexOutOfBoundsException If the specified {@code index} |
| 466 | * argument is negative, or if it is greater than or equal to |
| 467 | * the length of the specified array |
| 468 | * @see Array#set |
| 469 | */ |
| 470 | public static native void setDouble(Object array, int index, double d) |
| 471 | throws IllegalArgumentException, ArrayIndexOutOfBoundsException; |
| 472 | |
| 473 | /* |
| 474 | * Private |
| 475 | */ |
| 476 | |
| 477 | private static native Object newArray(Class componentType, int length) |
| 478 | throws NegativeArraySizeException; |
| 479 | |
| 480 | private static native Object multiNewArray(Class componentType, |
| 481 | int[] dimensions) |
| 482 | throws IllegalArgumentException, NegativeArraySizeException; |
| 483 | |
| 484 | |
| 485 | } |