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If you prefer not to use Bouncy Castle and want to rely on standard Java libraries, you can use the Java Cryptography Architecture (JCA) directly. Below is an example using the HKDF (HMAC-based Key Derivation Function) from the standard Java libraries:

```java
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Arrays;

public class HKDFExample {

    public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeyException {
        // Replace this with your actual master secret key
        byte[] masterSecretKey = hexStringToByteArray("yourMasterSecretKeyInHex");

        // Generate random salt (or use a fixed value depending on your use case)
        byte[] salt = generateSalt();

        // Derive encryption key (enck) and message authentication code key (mack)
        byte[] enck = hkdfExpand(masterSecretKey, salt, "ENCK".getBytes(StandardCharsets.UTF_8), 32); // 32 bytes for a 256-bit key
        byte[] mack = hkdfExpand(masterSecretKey, salt, "MACK".getBytes(StandardCharsets.UTF_8), 32); // 32 bytes for a 256-bit key

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

    private static byte[] generateSalt() {
        SecureRandom random = new SecureRandom();
        byte[] salt = new byte[16]; // Adjust the length as needed
        random.nextBytes(salt);
        return salt;
    }

    private static byte[] hkdfExpand(byte[] secret, byte[] salt, byte[] info, int length)
            throws NoSuchAlgorithmException, InvalidKeyException {
        Mac hmac = Mac.getInstance("HmacSHA256");
        SecretKeySpec keySpec = new SecretKeySpec(secret, "HmacSHA256");
        hmac.init(keySpec);

        byte[] prk = hmac.doFinal(salt);
        byte[] t = new byte[0];
        byte[] okm = new byte[length];

        for (int i = 0; i < (length + 255) / 256; i++) {
            hmac.reset();
            hmac.init(new SecretKeySpec(prk, "HmacSHA256"));
            hmac.update(t);
            hmac.update(info);
            hmac.update((byte) (i + 1));
            t = hmac.doFinal();

            int copyLength = Math.min(length, t.length);
            System.arraycopy(t, 0, okm, i * 256, copyLength);
            length -= copyLength;
        }

        return okm;
    }

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

This example uses the `HmacSHA256` algorithm to implement HKDF. Make sure to handle exceptions and errors appropriately in a production environment. Adjust the lengths and parameters according to your specific requirements.
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