Java Requires Chilkat v11.0.0+

JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signatures (JWS) using HMAC SHA-256. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.JsonObject;
import com.chilkatsoft.chilkat2.Jws;

public class ChilkatExample {

    public static void main(String[] args) {
        // This requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        // First create the JWS Protected Header
        JsonObject jwsProtHdr = new JsonObject();
        jwsProtHdr.appendString("typ", "JWT");
        jwsProtHdr.appendString("alg", "HS256");
        System.out.println("JWS Protected Header: " + jwsProtHdr.emit());

        // Output:
        // JWS Protected Header: {"typ":"JWT","alg":"HS256"}

        Jws jws = new Jws();

        // Set the HMAC key:
        String hmacKey = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow";
        int signatureIndex = 0;
        jws.setMacKey(signatureIndex, hmacKey, "base64url");

        // Set the protected header:
        jws.setProtectedHeader(signatureIndex, jwsProtHdr);

        // Set the payload.
        boolean bIncludeBom = false;
        String payloadStr = "In our village, folks say God crumbles up the old moon into stars.";
        jws.setPayload(payloadStr, "utf-8", bIncludeBom);

        // Create the JWS
        // By default, the compact serialization is used.
        String jwsCompact;
        try {
            jwsCompact = jws.createJws();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("JWS: " + jwsCompact);

        // sample output:
        // JWS: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.bsYsi8HJ0N6OqGI1hKQ9QQRNPxxA5qMpcHLtOvXatk8

        // Now load the JWS, validate, and recover the original text.
        Jws jws2 = new Jws();

        // Load the JWS.
        jws2.loadJws(jwsCompact);

        // Set the MAC key used for validation.
        signatureIndex = 0;
        jws2.setMacKey(signatureIndex, hmacKey, "base64url");

        // Validate the 1st (and only) signature at index 0..
        int v = jws2.validate(signatureIndex);
        if (v < 0) {
            // Perhaps Chilkat was not unlocked or the trial expired..
            System.out.println("Method call failed for some other reason.");
            System.out.println(jws2.getLastErrorText());
            return;
        }

        if (v == 0) {
            System.out.println("Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both.");
            return;
        }

        // If we get here, the signature was validated..
        System.out.println("Signature validated.");

        // Recover the original content:
        System.out.println(jws2.getPayload("utf-8"));

        // Examine the protected header:

        JsonObject joseHeader = new JsonObject();
        try {
            jws2.getProtectedH(signatureIndex, joseHeader);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        joseHeader.setEmitCompact(false);

        System.out.println("Protected (JOSE) header:");
        System.out.println(joseHeader.emit());

        // Output:

        //     Signature validated.
        //     In our village, folks say God crumbles up the old moon into stars.
        //     Protected (JOSE) header:
        //     {
        //       "typ": "JWT",
        //       "alg": "HS256"
        //     }
    }
}