Used to keep hash table capacities prime numbers.
Not of interest for users; only for implementors of hashtables.
Choosing prime numbers as hash table capacities is a good idea
to keep them working fast, particularly under hash table
expansions.
However, JDK 1.2, JGL 3.1 and many other toolkits do nothing to
keep capacities prime. This class provides efficient means to
choose prime capacities.
Choosing a prime is O(log 300) (binary search in a list
of 300 ints). Memory requirements: 1 KB static memory.
author: wolfgang.hoschek@cern.ch version: 1.0, 09/24/99 |