public static PGPSecretKey getSigningKey(Context context, long masterKeyId) { PGPSecretKeyRing keyRing = ProviderHelper.getPGPSecretKeyRingByMasterKeyId(context, masterKeyId); if (keyRing == null) { return null; } Vector<PGPSecretKey> signingKeys = getUsableSigningKeys(keyRing); if (signingKeys.size() == 0) { return null; } return signingKeys.get(0); }