Prerequisite : BigInteger Basics
The probablePrime() method will return a Biginteger of bitLength bits which is prime. bitLength is provided as parameter to method probablePrime() and method will return a prime BigInteger of bitLength bits. The probability that a BigInteger returned by this method is composite and does not exceed 2^-100.
Syntax:
public static BigInteger probablePrime(int bitLength, Random rnd)
Parameters: This method accepts two parameters as shown in the above syntax and described below.
- bitLength – bitLength of the returned BigInteger.
- rnd – source of random bits used to select candidates to be tested for primality.
Return Value: This method returns a BigInteger of bitLength bits that is probably prime.
Exception:
- ArithmeticException – if bitLength < 2.
Below program illustrate the probablePrime() method:
import java.math.*;
import java.util.Random;
import java.util.Scanner;
public class GFG {
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
// create a BigInteger object
BigInteger biginteger;
// create a integer value for bitLength
int length = 4 ;
// create a random object
Random random = new Random();
// call probablePrime method to find next probable prime
// whose bit length is equal to bitLength provided as parameter.
biginteger = BigInteger.probablePrime(length, random);
String result = "ProbablePrime whose bit length is "
+ length + " = " + biginteger;
// print result value
System.out.println(result);
}
} |
Output:
ProbablePrime whose bit length is 4 = 13