The API package 'memcache' or call 'FlushAll()' was not found

Question

I am testing some code locally using Google Apps Engine SDK 1.9.12. I have added a servlet listener to initialize memcache with 2 namespaces. I have added code inside the method contextDestroyed(ServletContextEvent sce) to clear the Memcache entries:

MemcacheServiceFactory.getMemcacheService().clearAll();

This actually throws the following exception and the server is down:

WARNING: EXCEPTION 
com.google.apphosting.api.ApiProxy$CallNotFoundException: The API package 'memcache' or call 'FlushAll()' was not found.
    at com.google.apphosting.api.ApiProxy$1.get(ApiProxy.java:179)
    at com.google.apphosting.api.ApiProxy$1.get(ApiProxy.java:177)
    at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:88)
    at com.google.appengine.api.memcache.MemcacheServiceImpl.quietGet(MemcacheServiceImpl.java:26)
    at com.google.appengine.api.memcache.MemcacheServiceImpl.clearAll(MemcacheServiceImpl.java:170)
    at com.valeo.general.util.BaseCacheManager.clearAll(BaseCacheManager.java:47)
    at com.valeo.general.listeners.BaseCacheListener.contextDestroyed(BaseCacheListener.java:27)
    at org.mortbay.jetty.handler.ContextHandler.doStop(ContextHandler.java:599)
    at org.mortbay.jetty.webapp.WebAppContext.doStop(WebAppContext.java:505)
    at org.mortbay.component.AbstractLifeCycle.stop(AbstractLifeCycle.java:76)
    at org.mortbay.jetty.handler.HandlerWrapper.doStop(HandlerWrapper.java:142)
    at org.mortbay.component.AbstractLifeCycle.stop(AbstractLifeCycle.java:76)
    at com.google.appengine.tools.development.JettyContainerService.reloadWebApp(JettyContainerService.java:393)
    at com.google.appengine.tools.development.JettyContainerService$2.filesChanged(JettyContainerService.java:380)
    at org.mortbay.util.Scanner.reportBulkChanges(Scanner.java:486)
    at org.mortbay.util.Scanner.reportDifferences(Scanner.java:352)
    at org.mortbay.util.Scanner.scan(Scanner.java:280)
    at org.mortbay.util.Scanner$1.run(Scanner.java:232)
    at java.util.TimerThread.mainLoop(Unknown Source)
    at java.util.TimerThread.run(Unknown Source)

Please help me to resolve this.

Answer 1

By the time the App Engine Java framework calls your code in contextDestroyed(ServletContextEvent) it has already torn down the connection to the backend services, including memcache.

So unfortunately you cannot use a ServletContextListener to perform memcache operations on shutdown.