jdd.util.math

Class Prime

java.lang.Object

jdd.util.math.Prime

public final class Prime
extends Object

prime-number support, mostly used in the hash-tables

note: we consider zero to not be a prime :(

Constructor Summary

Constructors

Constructor and Description
Prime()

Method Summary

Modifier and Type	Method and Description
static void	internal_test() testbench.
static boolean	isPrime(int n) prime test
static int	nextPrime(int n) get the closest prime larger than "n", including "n" itself
static int	prevPrime(int n) get the closest prime smaller than "n", including "n" itself

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Prime

public Prime()

Method Detail

isPrime

public static final boolean isPrime(int n)

prime test

Returns:

true if "n" is a prime number

nextPrime

public static final int nextPrime(int n)

get the closest prime larger than "n", including "n" itself

prevPrime

public static final int prevPrime(int n)

get the closest prime smaller than "n", including "n" itself

internal_test

public static void internal_test()

testbench. do not call