[FELIX-962] Erroneous class loading delegation to the application launcher classloader in some cases

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: framework-1.6.0
• Component/s: Framework
• Assignee: Richard S. Hall
• Reporter: Guillaume Nodet
• Created: 26/Feb/09 08:32
• Updated: 12/Mar/09 20:08
• Resolved: 12/Mar/09 19:52

Description

Here is an example stack trace:

ProcessStoreImpl-1@50 daemon, priority=5, in group 'main', status: 'RUNNING'
	  at org.apache.felix.framework.searchpolicy.ModuleImpl.searchDynamicImports(ModuleImpl.java:1,215)
	  at org.apache.felix.framework.searchpolicy.ModuleImpl.findClassOrResourceByDelegation(ModuleImpl.java:558)
	  at org.apache.felix.framework.searchpolicy.ModuleImpl.access$100(ModuleImpl.java:59)
	  at org.apache.felix.framework.searchpolicy.ModuleImpl$ModuleClassLoader.loadClass(ModuleImpl.java:1,382)
	  at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
	  at org.apache.felix.framework.searchpolicy.ModuleImpl.getClassByDelegation(ModuleImpl.java:428)
	  at org.apache.felix.framework.Felix.loadBundleClass(Felix.java:1,341)
	  at org.apache.felix.framework.BundleImpl.loadClass(BundleImpl.java:737)
	  at org.springframework.osgi.util.BundleDelegatingClassLoader.findClass(BundleDelegatingClassLoader.java:99)
	  at org.springframework.osgi.util.BundleDelegatingClassLoader.loadClass(BundleDelegatingClassLoader.java:156)
	  at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
	  at org.apache.xbean.classloader.MultiParentClassLoader.loadClass(MultiParentClassLoader.java:184)
	  at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
	  at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:374)
	  at java.lang.ClassLoader.defineClass1(ClassLoader.java:-1)
	  at java.lang.ClassLoader.defineClass(ClassLoader.java:675)
	  at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
	  at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
	  at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
	  at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
	  at java.security.AccessController.doPrivileged(AccessController.java:-1)
	  at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	  at org.apache.xbean.classloader.MultiParentClassLoader.loadClass(MultiParentClassLoader.java:200)
	  at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
	  at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:374)
	  at org.apache.openjpa.util.ProxyMaps.afterEntrySet(ProxyMaps.java:74)
	  at org.apache.openjpa.util.java$util$HashMap$proxy.entrySet(Unknown Source:-1)
	  at org.apache.openjpa.util.ProxyMaps.values(ProxyMaps.java:65)
	  at org.apache.openjpa.util.java$util$HashMap$proxy.values(Unknown Source:-1)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:335)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:283)
	  at org.apache.openjpa.kernel.StateManagerImpl.cascadeDelete(StateManagerImpl.java:2,861)
	  at org.apache.openjpa.kernel.BrokerImpl.delete(BrokerImpl.java:2,566)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:387)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:372)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:329)
	  at org.apache.openjpa.kernel.SingleFieldManager.delete(SingleFieldManager.java:283)
	  at org.apache.openjpa.kernel.StateManagerImpl.cascadeDelete(StateManagerImpl.java:2,861)
	  at org.apache.openjpa.kernel.BrokerImpl.delete(BrokerImpl.java:2,566)
	  at org.apache.openjpa.kernel.BrokerImpl.delete(BrokerImpl.java:2,531)
	  at org.apache.openjpa.kernel.DelegatingBroker.delete(DelegatingBroker.java:1,046)
	  at org.apache.openjpa.persistence.EntityManagerImpl.remove(EntityManagerImpl.java:659)
	  at org.apache.ode.store.jpa.JpaObj.delete(JpaObj.java:34)
	  at org.apache.ode.store.jpa.DeploymentUnitDaoImpl.delete(DeploymentUnitDaoImpl.java:114)
	  at org.apache.ode.store.ProcessStoreImpl$3.call(ProcessStoreImpl.java:303)
	  at org.apache.ode.store.ProcessStoreImpl$3.call(ProcessStoreImpl.java:300)
	  at org.apache.ode.store.ProcessStoreImpl$Callable.call(ProcessStoreImpl.java:701)
	  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:269)
	  at java.util.concurrent.FutureTask.run(FutureTask.java:123)
	  at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
	  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
	  at java.lang.Thread.run(Thread.java:613)

The interesting bit is the following exerpt:

	  at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
	  at java.security.AccessController.doPrivileged(AccessController.java:-1)
	  at java.net.URLClassLoader.findClass(URLClassLoader.java:188)

The current code in ModuleImpl#searchDynamicImports() does not really handle this case. The reason is that the java.net.URLClassLoader$1 class is an anonymous PrivilegedExceptionAction.
The result is that the loop is aborted too soon and the launcher classloader is used to delegate the call. In my application, it leads to all kinds of LinkageError being thrown.

Note that this problem mostly happen on macs, which has a weird thing in the classloader, trying to handle some org.apache.crimson / org.apache.xalan / org.apache.xml / org.apache.xpath in some weird way.
Anyway, I have a patch to support this anonymous classes I will attach now.