Log in to this provider.
The provider relies on a CallbackHandler
to obtain authentication information from the caller (a PIN, for example). If the caller passes a null
handler to this method, the provider uses the handler set in the setCallbackHandler
method. If no handler was set in that method, the provider queries the auth.login.defaultCallbackHandler security property for the fully qualified class name of a default handler implementation. If the security property is not set, the provider is assumed to have alternative means for obtaining authentication information.