Apex Legit CC Example

Main.java

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;

import javax.crypto.spec.SecretKeySpec;

import org.joda.time.DateTime;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;
import org.jose4j.jws.AlgorithmIdentifiers;
import org.jose4j.jws.JsonWebSignature;
import org.jose4j.lang.JoseException;

public class Main {

	public static void main(String[] args) throws JoseException, NoSuchAlgorithmException, InvalidKeyException {
		DateTime dt = new DateTime();
		DateTimeFormatter fmt = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SSSSSSZZ");
		JsonWebSignature jws = new JsonWebSignature();

		// Assign variables from provided credentials.json file
		String username = "";
		String entity = "";
		String secret = "";
		
		String payload = ("{'username': '" + username + "', 'datetime': '" + fmt.print(dt) + "', 'entity': '" + entity + "'}");
		// JSON in Java likes double-quotes instead of single
		payload = payload.replaceAll("'", "\"");

		// Create the secret key spec from the shared secret
		SecretKeySpec secretKey = new SecretKeySpec(secret.getBytes(), "HS512");

		// Set all the variables for the JWS
		jws.setKey(secretKey);
		jws.setPayload(payload);
		jws.setAlgorithmHeaderValue(AlgorithmIdentifiers.HMAC_SHA512);

		// Output the JWS string
		System.out.println(jws.getCompactSerialization());
	}
}