Generate Psuedo-Random Data using ARC4 as a PRNG

This example demonstrates how to use the ARC4 stream encryption algorithm as a pseudo-random number generator (PRNG). This example generates the random data as hex encoded strings. The EncryptStringENC method can be replaced with EncryptBytes to generate random bytes. Note: This example uses new features available in the pre-release, or any official new version released after 17-October-2007.

Download Chilkat Java Library

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    CkCrypt2 crypt = new CkCrypt2();

    boolean success;
    success = crypt.UnlockComponent("Anything for 30-day trial");
    if (success != true) {
        System.out.println("Crypt component unlock failed");
        return;
    }

    crypt.put_CryptAlgorithm("arc4");
    crypt.put_KeyLength(128);

    crypt.SetEncodedKey("000102030405060708090A0B0C0D0E0F","hex");

    crypt.put_EncodingMode("hex");

    //  We will repeatedly feed these 8-bytes of data to
    //  the ARC4 stream encryptor to generate our pseudo-random
    //  sequence.
    String strData;
    strData = "012345678";

    //  Set FirstChunk to true to initialize the ARC4 PRNG with the key.
    crypt.put_FirstChunk(true);
    crypt.put_LastChunk(false);

    String encryptedText;
    encryptedText = crypt.encryptStringENC(strData);
    System.out.println(encryptedText);

    //  Set FirstChunk to false to continue encrypting
    //  without re-initializing the ARC4 PRNG
    crypt.put_FirstChunk(false);

    int i;
    for (i = 1; i <= 16; i++) {
        //  Repeatedly encrypting the same 8 bytes of data
        //  produces then pseudo-random sequence.
        encryptedText = crypt.encryptStringENC(strData);
        System.out.println(encryptedText);
    }

  }
}