Java Requires Chilkat v11.0.0+

Validate JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Validates a JSON Web Signature (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.

        // This example takes a JSON signature in compact serialization format,
        // and uses a MAC key to validate and recover the protected header and payload.

        Jws jws = new Jws();

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

        // Load the JWS.
        String jwsCompact = "eyJ0eXAiOiJKV1QiLA0KICJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFtcGxlLmNvbS9pc19yb290Ijp0cnVlfQ.dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk";
        jws.loadJws(jwsCompact);

        // Validate the 1st (and only) signature at index 0..
        int v = jws.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(jws.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("Recovered content:");
        System.out.println(jws.getPayload("utf-8"));

        // Examine the protected header:

        JsonObject joseHeader = new JsonObject();
        try {
            jws.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.
        //     Recovered content:
        //     {"iss":"joe",
        //      "exp":1300819380,
        //      "http://example.com/is_root":true}
        //     Protected (JOSE) header:
        //     {
        //       "typ": "JWT",
        //       "alg": "HS256"
        //     }
    }
}