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If you want to derive separate keys for encryption (enck) and message authentication code (mack) from a master key using a Key Derivation Function (KDF), you can modify the previous example to derive two distinct keys. Here's an example:

```java
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import java.util.Arrays;

public class KDFEnckMackExample {

    public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeySpecException {
        // Replace with your master key
        byte[] masterKey = hexStringToByteArray("yourMasterKeyInHex");

        // Salt for KDF
        byte[] salt = generateSalt();

        // KDF parameters
        int iterationCount = 10000; // You can adjust this based on your security requirements
        int keyLength = 32; // for a 256-bit key

        // Use KDF to derive encryption key (enck)
        byte[] enck = deriveKey(masterKey, salt, iterationCount, keyLength);

        // Use KDF to derive message authentication code key (mack)
        byte[] mack = deriveKey(masterKey, salt, iterationCount, keyLength);

        // Print the derived keys
        System.out.println("Encryption Key (enck): " + byteArrayToHexString(enck));
        System.out.println("MAC Key (mack): " + byteArrayToHexString(mack));
    }

    private static byte[] generateSalt() {
        // Replace this with a secure method of generating salt
        // For example, you can use SecureRandom:
        // SecureRandom random = new SecureRandom();
        // byte[] salt = new byte[16];
        // random.nextBytes(salt);
        // return salt;
        return hexStringToByteArray("yourSaltInHex");
    }

    private static byte[] deriveKey(byte[] masterKey, byte[] salt, int iterationCount, int keyLength)
            throws NoSuchAlgorithmException, InvalidKeySpecException {
        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
        KeySpec spec = new PBEKeySpec(byteArrayToCharArray(masterKey), salt, iterationCount, keyLength * 8);
        return factory.generateSecret(spec).getEncoded();
    }

    private static byte[] hexStringToByteArray(String hex) {
        int len = hex.length();
        byte[] data = new byte[len / 2];
        for (int i = 0; i < len; i += 2) {
            data[i / 2] = (byte) ((Character.digit(hex.charAt(i), 16) << 4)
                    + Character.digit(hex.charAt(i + 1), 16));
        }
        return data;
    }

    private static char[] byteArrayToCharArray(byte[] byteArray) {
        char[] charArray = new char[byteArray.length];
        for (int i = 0; i < byteArray.length; i++) {
            charArray[i] = (char) (byteArray[i] & 0xFF);
        }
        return charArray;
    }

    private static String byteArrayToHexString(byte[] byteArray) {
        StringBuilder result = new StringBuilder();
        for (byte b : byteArray) {
            result.append(String.format("%02X", b));
        }
        return result.toString();
    }
}
```

In this example, the `deriveKey` method is called twice to derive two separate keys (`enck` and `mack`) from the master key. Ensure you replace "yourMasterKeyInHex" and "yourSaltInHex" with your actual master key and a random salt, respectively. Adjust the KDF parameters based on your security requirements.
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