docs: public Future<AuthenticationResult> acquireToken(final String resource,
              final ClientAssertion clientAssertion,
              final AuthenticationCallback callback) {
  
          this.validateInput(resource, clientAssertion, true);
          final ClientAuthentication clientAuth = createClientAuthFromClientAssertion(clientAssertion);
          final AdalOAuthAuthorizationGrant authGrant = new AdalOAuthAuthorizationGrant(
                  new ClientCredentialsGrant(), resource);
          return this.acquireToken(authGrant, clientAuth, callback);
      }