Products Google APIs for Android Reference com.google.android.gms.fido.u2f.api.messagebased Enums RequestType U2F request types ResponseType U2F response types Exceptions RequestType.UnsupportedRequestTypeException Exception thrown when an unsupported or unrecognized request type is encountered. Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 3.0 License, and code samples are licensed under the Apache 2.0 License. For details, see our Site Policies. Java is a registered trademark of Oracle and/or its affiliates. Last updated August 14, 2017.