I'm using Google App Engine (Java) and my war has to use TimedSemaphore to control resources within specific time period but GAE throws well-known exceptions due to accessed to disallowed API as follows.
java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "modifyThreadGroup")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:457)
at java.security.AccessController.checkPermission(AccessController.java:884)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at com.google.appengine.tools.development.DevAppServerFactory$CustomSecurityManager.checkPermission(DevAppServerFactory.java:429)
at com.google.appengine.tools.development.DevAppServerFactory$CustomSecurityManager.checkAccess(DevAppServerFactory.java:454)
at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:315)
at java.lang.Thread.init(Thread.java:389)
at java.lang.Thread.init(Thread.java:349)
at java.lang.Thread.<init>(Thread.java:674)
at java.util.concurrent.Executors$DefaultThreadFactory.newThread(Executors.java:613)
at java.util.concurrent.ThreadPoolExecutor$Worker.<init>(ThreadPoolExecutor.java:612)
at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:925)
at java.util.concurrent.ThreadPoolExecutor.ensurePrestart(ThreadPoolExecutor.java:1587)
at java.util.concurrent.ScheduledThreadPoolExecutor.delayedExecute(ScheduledThreadPoolExecutor.java:334)
at java.util.concurrent.ScheduledThreadPoolExecutor.scheduleAtFixedRate(ScheduledThreadPoolExecutor.java:573)
at org.apache.commons.lang3.concurrent.TimedSemaphore.startTimer(TimedSemaphore.java:404)
at org.apache.commons.lang3.concurrent.TimedSemaphore.acquire(TimedSemaphore.java:300)
However, as far as my understanding, The JRE Class White List contains all of classes called by TimedSemaphore.
My billing status is of course already active in order to use all features of GAE. Does anyone know why it happens?
