Ошибка Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException­: 0 at pr4.RSA.main(RSA.java:44)

package pr4;
 
import java.math.BigInteger;
import java.security.SecureRandom;
 
public class RSA {
    private final static BigInteger one = new BigInteger("1");
    private final static SecureRandom random = new SecureRandom();
 
    private BigInteger privateKey;
    private BigInteger publicKey;
    private BigInteger modulus;
 
    // generate an N-bit (roughly) public and private key
    RSA(int N) {
        BigInteger p = BigInteger.probablePrime(N / 2, random);
        BigInteger q = BigInteger.probablePrime(N / 2, random);
        BigInteger phi = (p.subtract(one)).multiply(q.subtract(one));
 
        modulus = p.multiply(q);
        publicKey = new BigInteger("65537"); // common value in practice = 2^16 + 1
        privateKey = publicKey.modInverse(phi);
    }
 
 
    BigInteger encrypt(BigInteger message) {
        return message.modPow(publicKey, modulus);
    }
 
    BigInteger decrypt(BigInteger encrypted) {
        return encrypted.modPow(privateKey, modulus);
    }
 
    public String toString() {
        String s = "";
        s += "public = " + publicKey + "\n";
        s += "private = " + privateKey + "\n";
        s += "modulus = " + modulus;
        return s;
    }
 
    public static void main(String[] args) {
        if (args.length == 0) {
            args = new String[]{"10"};  //  здесь задается число
        }
        int N = Integer.parseInt(args[0]);
        RSA key = new RSA(N);
        System.out.println(key);
 
// create random message, encrypt and decrypt
        BigInteger message = new BigInteger(N - 1, random);
 
//// create message by converting string to integer
// String s = "test";
// byte[] bytes = s.getBytes();
// BigInteger message = new BigInteger(s);
 
        BigInteger encrypt = key.encrypt(message);
        BigInteger decrypt = key.decrypt(encrypt);
        System.out.println("message = " + message);
        System.out.println("encrpyted = " + encrypt);
        System.out.println("decrypted = " + decrypt);
    }
}