http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.jcajce.provider.asymmetric.util;

public class PrimeCertaintyCalculator
{
    private PrimeCertaintyCalculator()
    {

    }

    
Return the current wisdom on prime certainty requirements.

Params:
  • keySizeInBits – size of the key being generated.
Returns:a certainty value.
/**
     * Return the current wisdom on prime certainty requirements.
     *
     * @param keySizeInBits size of the key being generated.
     * @return a certainty value.
     */
    public static int getDefaultCertainty(int keySizeInBits)
    {
        // Based on FIPS 186-4 Table C.1
        return keySizeInBits <= 1024 ? 80 : (96 + 16 * ((keySizeInBits - 1) / 1024));
    }
}