public BigInteger(int bitLength, int certainty, Random rnd) Constructs a randomly generated positive BigInteger that is probably prime, with the specified bitLength.It is recommended that the probablePrime method be used in preference to this constructor unless there is a compelling need to specify a certainty.
Parameters: bitLength - bitLength of the returned BigInteger.certainty - a measure of the uncertainty that the caller is willing to tolerate. The probability that the new BigInteger represents a prime number will exceed (1 - 1/2certainty). The execution time of this constructor is proportional to the value of this parameter.rnd - source of random bits used to select candidates to be tested for primality. Throws: ArithmeticException - bitLength < 2
java.math.BigInteger
java.math.BigInteger(byte[])
java.math.BigInteger(int, byte[])
java.math.BigInteger(int, int, java.util.Random)
java.math.BigInteger(int, java.util.Random)
java.math.BigInteger(java.lang.String)
java.math.BigInteger(java.lang.String, int)
int certainty,
Random rnd) Constructs a randomly generated positive BigInteger that is probably prime, with the specified bitLength.It is recommended that the probablePrime method be used in preference to this constructor unless there is a compelling need to specify a certainty.
Parameters:
bitLength - bitLength of the returned BigInteger.certainty - a measure of the uncertainty that the caller is willing to tolerate. The probability that the new BigInteger represents a prime number will exceed (1 - 1/2certainty). The execution time of this constructor is proportional to the value of this parameter.rnd - source of random bits used to select candidates to be tested for primality. Throws: ArithmeticException - bitLength < 2
意思是不是随机产生随机bit用来判断那些产生的大数是不是素数?