[KARAF-5674] Karaf 4.2.0 M2 class load issue

• Type: Bug
• Status: Open
• Priority: Critical
• Resolution: Unresolved
• Affects Version/s: 4.2.0.M2
• Component/s: karaf
• Assignee: Unassigned
• Reporter: Boban Petkovic
• Created: 20/Mar/18 16:08
• Updated: 19/Dec/19 17:36

Description

While migrating our application to work on karaf 4.2.0 (once it got released) I hit an issue with class loader while testing on karaf 4.2.0 M2. I will try to explain it simple:

Let say I have bundle A that contains REST endpoints (CXF 3.2.2). I use dosgi to register CXF endpoints. From REST endpoint (in bundle A) we invoke some code from bundle B that uses aws-java-sdk-osgi bundle (version 1.11.272). This fails with the error:

javax.xml.stream.XMLInputFactory: Provider com.ctc.wstx.stax.WstxInputFactory not found

The same code works on karaf 4.1.5 and karaf 4.0.7 that we use at the moment. After some investigation I figured out that the context of class loader used to invoke the code from our bundles is org.apache.cxf.cxf-rt-transports-http. When I tried to set class loader to use our bundle's context it worked fine:

ClassLoader tccl = Thread.currentThread() .getContextClassLoader(); Thread.currentThread().setContextClassLoader(this.getClass().getClassLoader());
AWS SDK calls that fails (from bundle B) 
Thread.currentThread().setContextClassLoader(tccl);

Has something been changed when it comes to class loading mechanism in 4.2.0? While testing the same code on 4.1.5 I can see that the same context (org.apache.cxf.cxf-rt-transports-http) is used, but it works fine.

Issue Links

• requires: KARAF-5680 Provide support for xml parsers deployed as bundle on Java 9