public int next() {
      int t = x ^ (x << 11);
      x = y;
      y = z;
      z = w;
      return w = (w ^ (w >>> 19) ^ (t ^ (t >>> 8)));
    }
Multiplication-free RNG from Marsaglia "Xorshift RNGs" paper
geode-junit/src/main/java/org/apache/geode/internal/util/concurrent/cm/LoopHelpers.java