ThreadLocalRandom setSeed

Question

Is it possible to provide a Seed to a ThreadLocalRandom?

/**
 * Throws {@code UnsupportedOperationException}.  Setting seeds in
 * this generator is not supported.
 *
 * @throws UnsupportedOperationException always
 */
public void setSeed(long seed) {
    if (initialized)
        throw new UnsupportedOperationException();
    rnd = (seed ^ multiplier) & mask;
}

So can we use ThreadLocalRandom using seed or it's not designed for that?

Why look at implementation when the public specification already gives you the answer? `Like the global {@link java.util.Random} generator used by the {@link java.lang.Math} class, a {@code ThreadLocalRandom} is initialized with an internally generated seed that may not otherwise be modified.` — Marko Topolnik, Oct 03 '16 at 13:57

score 12 · Answer 1 · answered Mar 19 '19 at 10:48

12

As @Marko Topolnik commented, ThreadLocalRandom does not allow to set your own seed. You can bypass this problem by using a ThreadLocal<Random>, as discussed in this question.

answered Mar 19 '19 at 10:48

fidekild

161
3
13

This should be a comment. – wscourge Mar 19 '19 at 11:06
@wscourge Ok thank you, I did not have enough reputation to comment but I had the same question and found the link useful in my case. – fidekild Mar 19 '19 at 12:44
10

@wscourge No, it deserves to be a useful answer. – John McClane Sep 20 '20 at 15:59

ThreadLocalRandom setSeed

1 Answers1