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root/jsr166/jsr166/src/main/java/util/SplittableRandom.java
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Comparing jsr166/src/main/java/util/SplittableRandom.java (file contents):
Revision 1.28 by jsr166, Sat Sep 19 21:07:10 2015 UTC vs.
Revision 1.41 by jsr166, Sun Dec 2 23:06:16 2018 UTC

# Line 80 | Line 80 | import java.util.stream.StreamSupport;
80   * in security-sensitive applications. Additionally,
81   * default-constructed instances do not use a cryptographically random
82   * seed unless the {@linkplain System#getProperty system property}
83 < * {@code java.util.secureRandomSeed} is set to {@code true}.
83 > * {@systemProperty java.util.secureRandomSeed} is set to {@code true}.
84   *
85   * @author  Guy Steele
86   * @author  Doug Lea
# Line 219 | Line 219 | public final class SplittableRandom {
219          return seed += gamma;
220      }
221  
222 +    // IllegalArgumentException messages
223 +    static final String BAD_BOUND = "bound must be positive";
224 +    static final String BAD_RANGE = "bound must be greater than origin";
225 +    static final String BAD_SIZE  = "size must be non-negative";
226 +
227      /**
228       * The seed generator for default constructors.
229       */
230 <    private static final AtomicLong defaultGen = new AtomicLong(initialSeed());
231 <
232 <    private static long initialSeed() {
233 <        String pp = java.security.AccessController.doPrivileged(
234 <                new sun.security.action.GetPropertyAction(
235 <                        "java.util.secureRandomSeed"));
236 <        if (pp != null && pp.equalsIgnoreCase("true")) {
230 >    private static final AtomicLong defaultGen
231 >        = new AtomicLong(mix64(System.currentTimeMillis()) ^
232 >                         mix64(System.nanoTime()));
233 >
234 >    // at end of <clinit> to survive static initialization circularity
235 >    static {
236 >        if (java.security.AccessController.doPrivileged(
237 >            new java.security.PrivilegedAction<Boolean>() {
238 >                public Boolean run() {
239 >                    return Boolean.getBoolean("java.util.secureRandomSeed");
240 >                }})) {
241              byte[] seedBytes = java.security.SecureRandom.getSeed(8);
242 <            long s = (long)(seedBytes[0]) & 0xffL;
242 >            long s = (long)seedBytes[0] & 0xffL;
243              for (int i = 1; i < 8; ++i)
244 <                s = (s << 8) | ((long)(seedBytes[i]) & 0xffL);
245 <            return s;
244 >                s = (s << 8) | ((long)seedBytes[i] & 0xffL);
245 >            defaultGen.set(s);
246          }
238        return (mix64(System.currentTimeMillis()) ^
239                mix64(System.nanoTime()));
247      }
248  
242    // IllegalArgumentException messages
243    static final String BAD_BOUND = "bound must be positive";
244    static final String BAD_RANGE = "bound must be greater than origin";
245    static final String BAD_SIZE  = "size must be non-negative";
246
249      /*
250       * Internal versions of nextX methods used by streams, as well as
251       * the public nextX(origin, bound) methods.  These exist mainly to
# Line 373 | Line 375 | public final class SplittableRandom {
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      }
# Line 397 | Line 399 | public final class SplittableRandom {
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
# Line 777 | Line 799 | public final class SplittableRandom {
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
781 <     * @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,
# Line 825 | Line 846 | public final class SplittableRandom {
846       * approach. The long and double versions of this class are
847       * identical except for types.
848       */
849 <    static final class RandomIntsSpliterator implements Spliterator.OfInt {
849 >    private static final class RandomIntsSpliterator
850 >            implements Spliterator.OfInt {
851          final SplittableRandom rng;
852          long index;
853          final long fence;
# Line 880 | Line 902 | public final class SplittableRandom {
902      /**
903       * Spliterator for long streams.
904       */
905 <    static final class RandomLongsSpliterator implements Spliterator.OfLong {
905 >    private static final class RandomLongsSpliterator
906 >            implements Spliterator.OfLong {
907          final SplittableRandom rng;
908          long index;
909          final long fence;
# Line 936 | Line 959 | public final class SplittableRandom {
959      /**
960       * Spliterator for double streams.
961       */
962 <    static final class RandomDoublesSpliterator implements Spliterator.OfDouble {
962 >    private static final class RandomDoublesSpliterator
963 >            implements Spliterator.OfDouble {
964          final SplittableRandom rng;
965          long index;
966          final long fence;

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