Random Numbers not playing fair!

Question

Hi All.
Can anyone explain why I keep getting the same number out of the Random class? Each time I run my program, I get a different number, but it then repeats that same 'random' number. I've tried using the Math.random and that didn't seem to work either.
Thanks
Dr Nick

Answer 1

This "repeating the same number" problem of Random is
usually because it's instantiated many times in a
loop. Random takes its seed from the system clock with
a resolution of 1 millisecond. If random is
instantiated many times during 1 millisecond it will
use the same seed and thus deliver the same random
numbers.That's all true, but he said he experienced this with java.lang.Math.random() which reuses the same random number generator. Here's the source for it:
    public static double random() {
        if (randomNumberGenerator == null) initRNG();
        return randomNumberGenerator.nextDouble();
    }"randomNumberGenerator" is static.