You will have a very hard time to get a TransportClient working on GAE due
to the sandbox restrictions outlined
in https://developers.google.com/appengine/docs/java/runtime#The_Sandbox
The most promising approach would be a complete rewrite of a Java client,
simplifying the TransportClient, by utilizing the HTTP URL methods of the
GAE SDK instead of Netty and the related thread pooling, and mimicking a
single-threaded HTTP REST client.
Jörg
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