Bouncy Casle in J2ME

Question

Hi I have done encryptionin bouncycastle algorithm but it tells the following error:
ERROR:
java.lang.NoClassDefFoundError: java/security/SecureRandom: Cannot create class in system package
PROGRAM:
import java.math.BigInteger;
import java.security.SecureRandom;
import org.bouncycastle.crypto.AsymmetricBlockCipher;
import org.bouncycastle.crypto.AsymmetricCipherKeyPair;
import org.bouncycastle.crypto.encodings.PKCS1Encoding;
import org.bouncycastle.crypto.engines.RSAEngine;
import org.bouncycastle.crypto.generators.RSAKeyPairGenerator;
import org.bouncycastle.crypto.params.RSAKeyGenerationParameters;
import org.bouncycastle.crypto.params.RSAKeyParameters;
import org.bouncycastle.crypto.params.RSAPrivateCrtKeyParameters;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class Encryption extends MIDlet implements CommandListener
     Form f = new Form("MyForm");
     Command okCmd = new Command("Ok",Command.OK,1);
     Command exitCmd = new Command("Exit",Command.EXIT,2);
     private RSAPrivateCrtKeyParameters _RSAPrivateKey;
     private RSAKeyParameters _RSAPublicKey;
     public void startApp()
          f.addCommand(okCmd);
          f.addCommand(exitCmd);
          f.setCommandListener(this);
          Display.getDisplay(this).setCurrent(f);
     public void pauseApp()
     public void destroyApp(boolean unconditional)
     public void commandAction(Command c, Displayable d)
          if (c == okCmd)
               functionCall();
          if (c == exitCmd)
               notifyDestroyed();
     void functionCall()
          String theStringBeforeEncryption = "String to encrypt";
          String theStringAfterEncryption = null;
          byte[] theEncryptedString;
          try
               System.out.println(theStringBeforeEncryption);
               generateRSAKeyPair();
               theEncryptedString = RSAEncrypt(theStringBeforeEncryption.getBytes());
               theStringAfterEncryption = new String(RSADecrypt(theEncryptedString));
               System.out.println(theStringAfterEncryption);
          catch (Exception e)
               // TODO Handle exception!
               e.printStackTrace();
     }//end of functionCall()
     private void generateRSAKeyPair () throws Exception
          SecureRandom theSecureRandom = new SecureRandom();
          BigInteger thePublicExponent = new BigInteger("10001", 16);
          RSAKeyGenerationParameters theRSAKeyGenParam =
               new RSAKeyGenerationParameters(thePublicExponent, theSecureRandom, 1024, 80);
          RSAKeyPairGenerator theRSAKeyPairGen = new RSAKeyPairGenerator();
          theRSAKeyPairGen.init(theRSAKeyGenParam);
          AsymmetricCipherKeyPair theKeyPair = theRSAKeyPairGen.generateKeyPair();
          _RSAPrivateKey = (RSAPrivateCrtKeyParameters) theKeyPair.getPrivate();
          _RSAPublicKey = (RSAKeyParameters) theKeyPair.getPublic();
     private byte [] RSAEncrypt (byte [] toEncrypt) throws Exception
          if (_RSAPublicKey == null)
               throw new Exception("Please generate RSA keys first in order to work");
          AsymmetricBlockCipher theEngine = new RSAEngine();
          theEngine = new PKCS1Encoding(theEngine);
          theEngine.init(true, _RSAPublicKey);
          return theEngine.processBlock(toEncrypt, 0, toEncrypt.length);
     private byte [] RSADecrypt (byte [] toDecrypt) throws Exception
          if (_RSAPrivateKey == null)
               throw new Exception("Please generate RSA keys first in order to work");
          AsymmetricBlockCipher theEngine = new RSAEngine();
          theEngine = new PKCS1Encoding(theEngine);
          theEngine.init(false, _RSAPrivateKey);
          return theEngine.processBlock(toDecrypt, 0, toDecrypt.length);
please Help me
Regards,
Nelson

Answer 1

There is no class by name "SecureRandom" in "java.security" package as far as CLDC/MIDP API's available for the application developer are concerned with.
May be you need to check out the alternative for SecureRandom class provided by the J2ME implementation of the BouncyCastle API.
~Mohan