[FELIX-4727] WrappedResource.getCapabilities ignores the namespace param

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: resolver-1.2.0
• Component/s: Resolver
• Environment: All
• Assignee: Richard S. Hall
• Reporter: Tom Watson
• Created: 11/Dec/14 15:30
• Updated: 15/Dec/14 14:17
• Resolved: 12/Dec/14 20:53

Description

The overall design of org.apache.felix.resolver.WrappedResource is that it is an internal type to the ResolverImpl and is not exposed to external code. The fact that it does not pay attention to the namespace param is an oversite, but not one that effects the ResolverImpl since it uses a null param anyway and does its own filtering of the capabilities.

But there are cases where this type will get exposed to code outside the resolver implementation. One example is when ResolverImpl.mergeUses is called and does a ArrayList.contains. Typically the types in the list are provided by the ResolveContext implementation. If a WrappedCapability is passed to the ArrayList.contains method then it does an equals call across all values in the list. If a ResolveContext capability implementation of that equals method calls getResource on WrappedCapability then it will be exposed to the WrappedResource. I know of one case where this causes issues when the client code is trying to get the osgi.identity capability of the WrappedResource. All capabilities are being returned but the first one is not the expected osgi.identity.

Here is a stacktrace from Aries:

Caused by: java.lang.NullPointerException
at org.apache.aries.subsystem.obr.internal.FelixResourceAdapter.equals(FelixResourceAdapter.java:44)
at java.util.ArrayList.indexOf(ArrayList.java:319)
at java.util.ArrayList.contains(ArrayList.java:302)
at org.apache.felix.resolver.ResolverImpl.mergeUses(ResolverImpl.java:955)
at org.apache.felix.resolver.ResolverImpl.calculatePackageSpaces(ResolverImpl.java:767)
at org.apache.felix.resolver.ResolverImpl.calculatePackageSpaces(ResolverImpl.java:715)
at org.apache.felix.resolver.ResolverImpl.calculatePackageSpaces(ResolverImpl.java:715)
at org.apache.felix.resolver.ResolverImpl.calculatePackageSpaces(ResolverImpl.java:715)
at org.apache.felix.resolver.ResolverImpl.resolve(ResolverImpl.java:249)
at org.apache.aries.subsystem.core.internal.SubsystemResource.computeDependencies(SubsystemResource.java:410)
at org.apache.aries.subsystem.core.internal.SubsystemResource.computeDependencies(SubsystemResource.java:393)
at org.apache.aries.subsystem.core.internal.SubsystemResource.<init>(SubsystemResource.java:101)
at org.apache.aries.subsystem.core.internal.SubsystemResource.<init>(SubsystemResource.java:92)
at org.apache.aries.subsystem.core.internal.InstallAction.createSubsystemResource(InstallAction.java:128)
at org.apache.aries.subsystem.core.internal.InstallAction.run(InstallAction.java:62)