| 375 |
|
* may, and typically does, vary across program invocations. |
| 376 |
|
*/ |
| 377 |
|
public SplittableRandom() { // emulate defaultGen.split() |
| 378 |
< |
long s = defaultGen.getAndAdd(2 * GOLDEN_GAMMA); |
| 378 |
> |
long s = defaultGen.getAndAdd(GOLDEN_GAMMA << 1); |
| 379 |
|
this.seed = mix64(s); |
| 380 |
|
this.gamma = mixGamma(s + GOLDEN_GAMMA); |
| 381 |
|
} |
| 399 |
|
} |
| 400 |
|
|
| 401 |
|
/** |
| 402 |
+ |
* Fills a user-supplied byte array with generated pseudorandom bytes. |
| 403 |
+ |
* |
| 404 |
+ |
* @param bytes the byte array to fill with pseudorandom bytes |
| 405 |
+ |
* @throws NullPointerException if bytes is null |
| 406 |
+ |
* @since 10 |
| 407 |
+ |
*/ |
| 408 |
+ |
public void nextBytes(byte[] bytes) { |
| 409 |
+ |
int i = 0; |
| 410 |
+ |
int len = bytes.length; |
| 411 |
+ |
for (int words = len >> 3; words--> 0; ) { |
| 412 |
+ |
long rnd = nextLong(); |
| 413 |
+ |
for (int n = 8; n--> 0; rnd >>>= Byte.SIZE) |
| 414 |
+ |
bytes[i++] = (byte)rnd; |
| 415 |
+ |
} |
| 416 |
+ |
if (i < len) |
| 417 |
+ |
for (long rnd = nextLong(); i < len; rnd >>>= Byte.SIZE) |
| 418 |
+ |
bytes[i++] = (byte)rnd; |
| 419 |
+ |
} |
| 420 |
+ |
|
| 421 |
+ |
/** |
| 422 |
|
* Returns a pseudorandom {@code int} value. |
| 423 |
|
* |
| 424 |
|
* @return a pseudorandom {@code int} value |
| 550 |
|
Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1); |
| 551 |
|
} |
| 552 |
|
|
| 533 |
– |
/** |
| 534 |
– |
* Generates a pseudorandom number with the indicated number of |
| 535 |
– |
* bits. Unlike in superclass @{link Random}, this method is never |
| 536 |
– |
* internally called or used by any other publicly accessible |
| 537 |
– |
* method. |
| 538 |
– |
* |
| 539 |
– |
* @param bits random bits |
| 540 |
– |
* @return the next pseudorandom value from this random number |
| 541 |
– |
* generator's sequence |
| 542 |
– |
*/ |
| 543 |
– |
protected int next(int bits) { |
| 544 |
– |
return (int)(nextLong() >>> (64 - bits)); |
| 545 |
– |
} |
| 546 |
– |
|
| 553 |
|
/** |
| 554 |
|
* Returns a pseudorandom {@code double} value between the specified |
| 555 |
|
* origin (inclusive) and bound (exclusive). |
| 799 |
|
* @return a stream of pseudorandom {@code double} values, |
| 800 |
|
* each with the given origin (inclusive) and bound (exclusive) |
| 801 |
|
* @throws IllegalArgumentException if {@code streamSize} is |
| 802 |
< |
* less than zero |
| 797 |
< |
* @throws IllegalArgumentException if {@code randomNumberOrigin} |
| 802 |
> |
* less than zero, or {@code randomNumberOrigin} |
| 803 |
|
* is greater than or equal to {@code randomNumberBound} |
| 804 |
|
*/ |
| 805 |
|
public DoubleStream doubles(long streamSize, double randomNumberOrigin, |
