| 307 |
|
return al.iterator(); |
| 308 |
|
} |
| 309 |
|
|
| 310 |
+ |
/** |
| 311 |
+ |
* Compares the specified object with this set for equality. |
| 312 |
+ |
* Returns <tt>true</tt> if the specified object is also a set, |
| 313 |
+ |
* and every element of the specified set, as revealed by a single |
| 314 |
+ |
* traversal of its <tt>iterator()</tt>, is also contained in this |
| 315 |
+ |
* set at the point of call of this method, and no other elements |
| 316 |
+ |
* not present in the given set are contained in this set. |
| 317 |
+ |
* |
| 318 |
+ |
* @param o object to be compared for equality with this set |
| 319 |
+ |
* @return <tt>true</tt> if the specified object is equal to this set |
| 320 |
+ |
*/ |
| 321 |
+ |
public boolean equals(Object o) { |
| 322 |
+ |
if (o == this) |
| 323 |
+ |
return true; |
| 324 |
+ |
if (!(o instanceof Set)) |
| 325 |
+ |
return false; |
| 326 |
+ |
Set<?> set = (Set<?>)(o); |
| 327 |
+ |
Iterator<?> setIt = set.iterator(); |
| 328 |
+ |
|
| 329 |
+ |
// Uses O(n^2) algorithm that is only appropriate |
| 330 |
+ |
// for small sets, which CopyOnWriteArraySets should be. |
| 331 |
+ |
|
| 332 |
+ |
// Use a single snapshot of underlying array |
| 333 |
+ |
Object[] elements = al.getArray(); |
| 334 |
+ |
int len = elements.length; |
| 335 |
+ |
// Mark matched elements to avoid re-checking |
| 336 |
+ |
boolean[] matched = new boolean[len]; |
| 337 |
+ |
int k = 0; |
| 338 |
+ |
while (setIt.hasNext()) { |
| 339 |
+ |
if (++k > len) |
| 340 |
+ |
return false; |
| 341 |
+ |
Object x = setIt.next(); |
| 342 |
+ |
boolean found = false; |
| 343 |
+ |
for (int i = 0; i < len; ++i) { |
| 344 |
+ |
if (!matched[i] && eq(x, elements[i])) { |
| 345 |
+ |
matched[i] = true; |
| 346 |
+ |
found = true; |
| 347 |
+ |
break; |
| 348 |
+ |
} |
| 349 |
+ |
} |
| 350 |
+ |
if (!found) |
| 351 |
+ |
return false; |
| 352 |
+ |
} |
| 353 |
+ |
return k == len; |
| 354 |
+ |
} |
| 355 |
+ |
|
| 356 |
+ |
/** |
| 357 |
+ |
* Test for equality, coping with nulls. |
| 358 |
+ |
*/ |
| 359 |
+ |
private static boolean eq(Object o1, Object o2) { |
| 360 |
+ |
return (o1 == null ? o2 == null : o1.equals(o2)); |
| 361 |
+ |
} |
| 362 |
+ |
|
| 363 |
|
} |
