RSA algorithm using threads

import java.security.KeyPairGenerator;
import java.security.KeyPair;
import java.security.PublicKey;
import java.security.PrivateKey;
import javax.crypto.Cipher;
public class rsa {
  private static byte[] encrypt(byte[] inpBytes, PublicKey key,
      String xform) throws Exception {
    Cipher cipher = Cipher.getInstance(xform);
    cipher.init(Cipher.ENCRYPT_MODE, key);
    return cipher.doFinal(inpBytes);
  }
  private static byte[] decrypt(byte[] inpBytes, PrivateKey key,
      String xform) throws Exception{
    Cipher cipher = Cipher.getInstance(xform);
    cipher.init(Cipher.DECRYPT_MODE, key);
    return cipher.doFinal(inpBytes);
  }
  public static void main(String[] unused) throws Exception {
   long starttime =System.currentTimeMillis();
   
   String xform = "RSA/NONE/PKCS1PADDING";
    // Generate a key-pair
    KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");
    kpg.initialize(1024); // 1024 is the keysize.
    KeyPair kp = kpg.generateKeyPair();
    PublicKey pubk = kp.getPublic();
    PrivateKey prvk = kp.getPrivate();
    byte[] dataBytes =
        "J2EE Security for Servlets, EJBs and Web Services".getBytes();
    byte[] encBytes = encrypt(dataBytes, pubk, xform);
    System.out.println(encBytes);
    byte[] decBytes = decrypt(encBytes, prvk, xform);
    System.out.println(decBytes);
    String res=new String(decBytes);
    
    boolean expected = java.util.Arrays.equals(dataBytes, decBytes);
    System.out.println("Test " + (expected ? "SUCCEEDED!" : "FAILED!"));
    System.out.println(res);
    long endtime=System.currentTimeMillis();
System.out.println("Time required for sequential rsa algorithm:"+(endtime-starttime)+"millisecond");
  }
}