How to Use Unsupported Exception for Lower Platform Version

Question

I have a DialogFragment that handles login and fingerprint authentication for my application. This fragment uses two classes that are exclusive to API 23,

Answer 1

As you said the problem is with that catch block

catch (KeyPermanentlyInvalidatedException exception) {
    Timber.w(exception, "A new fingerprint was added to the device");
    handleKeyPermanentlyInvalidated();
    return false;
}

Because that exception is added on API LEVEL 23, but I don't know why the verify error is thrown at initialization time itself.

Anyway you can catch the exception using

catch (InvalidKeyExceptionexception) {
    ....
    return false;
}

since KeyPermanentlyInvalidatedException extends InvalidKeyExceptionexception