jetty9-compat + java8 構成を使用すると、次の例外が発生します。おそらくこれが原因で、オブジェクトをセッションに保存できないため、最終的にサービスにログインできません。
[INFO] cze 28, 2016 11:17:56 AM com.google.apphosting.vmruntime.VmMetadataCache getMetadata
[INFO]
[INFO] INFO: Meta-data 'attributes/gae_affinity' path retrieval error: metadata
[INFO]
[INFO] cze 28, 2016 11:17:56 AM com.google.apphosting.vmruntime.VmApiProxyDelegate runSyncCall
[INFO]
[INFO] INFO: HTTP ApiProxy I/O error for memcache.Get: The target server failed to respond
[INFO]
[INFO] cze 28, 2016 11:17:56 AM com.google.appengine.api.memcache.LogAndContinueErrorHandler handleServiceError
[INFO]
[INFO] INFO: Service error in memcache
[INFO]
[INFO] com.google.appengine.api.memcache.MemcacheServiceException: RCP Failure for API call: memcache Get
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate.constructApiException(VmApiProxyDelegate.java:232)
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate.runSyncCall(VmApiProxyDelegate.java:195)
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate.makeApiCall(VmApiProxyDelegate.java:154)
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate.access$000(VmApiProxyDelegate.java:60)
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate$MakeSyncCall.call(VmApiProxyDelegate.java:436)
[INFO]
[INFO] at com.google.apphosting.vmruntime.VmApiProxyDelegate$MakeSyncCall.call(VmApiProxyDelegate.java:412)
[INFO]
[INFO] at java.util.concurrent.FutureTask.run(FutureTask.java:266)
[INFO]
[INFO] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
[INFO]
[INFO] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[INFO]
[INFO] at java.lang.Thread.run(Thread.java:745)
[INFO]
[INFO]
[INFO]
[INFO] DEBUG 2016-06-28 11:17:56,493 api_server.py:277] Handled datastore_v3.Get in 0.0000
[INFO] cze 28, 2016 11:17:59 AM com.mysql.jdbc.log.Slf4JLogger logInfo