Android™
Android™
Sign a JWS with an HMAC Key from BinData
See more JSON Web Signatures (JWS) Examples
Demonstrates Jws.SetMacKeyBd, which sets the symmetric MAC key for a signature from the raw bytes in a BinData.
Background. This is the in-memory equivalent of SetMacKey, for when the key material is already available as bytes.
Chilkat Android™ Downloads
// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;
import android.app.Activity;
import com.chilkatsoft.*;
import android.widget.TextView;
import android.os.Bundle;
public class SimpleActivity extends Activity {
private static final String TAG = "Chilkat";
// Called when the activity is first created.
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
boolean success = false;
CkJws jws = new CkJws();
// Protected header specifying HMAC-SHA256.
CkJsonObject header = new CkJsonObject();
header.UpdateString("alg","HS256");
success = jws.SetProtectedHeader(0,header);
if (success == false) {
Log.i(TAG, jws.lastErrorText());
return;
}
boolean bIncludeBom = false;
success = jws.SetPayload("This is the content to sign.","utf-8",bIncludeBom);
if (success == false) {
Log.i(TAG, jws.lastErrorText());
return;
}
// Set the symmetric MAC key for signature 0 from the raw bytes in a BinData. In production, obtain
// the key material from a secure source.
CkBinData bdKey = new CkBinData();
bdKey.AppendEncoded("YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=","base64");
success = jws.SetMacKeyBd(0,bdKey);
if (success == false) {
Log.i(TAG, jws.lastErrorText());
return;
}
String jwsCompact = jws.createJws();
if (jws.get_LastMethodSuccess() == false) {
Log.i(TAG, jws.lastErrorText());
return;
}
Log.i(TAG, jwsCompact);
}
static {
System.loadLibrary("chilkat");
// Note: If the incorrect library name is passed to System.loadLibrary,
// then you will see the following error message at application startup:
//"The application <your-application-name> has stopped unexpectedly. Please try again."
}
}