Creating Digital Signature

package bouncyCastle;

import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.Signature;
import java.util.Scanner;

public class CreatingDigitalSignature {
	public static void main(String args[]) throws Exception {
		// Accepting text from user
		Scanner sc = new Scanner(System.in);
		System.out.println("Enter some text");
		String msg = sc.nextLine();

		// Creating KeyPair generator object
		KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("DSA");

		// Initializing the key pair generator
		keyPairGen.initialize(2048);

		// Generate the pair of keys
		KeyPair pair = keyPairGen.generateKeyPair();

		// Getting the private key from the key pair
		PrivateKey privKey = pair.getPrivate();

		// Creating a Signature object
		Signature sign = Signature.getInstance("SHA256withDSA");

		// Initialize the signature
		sign.initSign(privKey);
		byte[] bytes = "msg".getBytes();

		// Adding data to the signature
		sign.update(bytes);

		// Calculating the signature
		byte[] signature = sign.sign();

		// Printing the signature
		System.out.println("Digital signature for given text: " + new String(signature, "UTF8"));
	}
}