Brooklyn has a number of places where it will try to load a class by name. It's either using Class.forName(..) or at best mgmt.getCatalogClassLoader().loadClass(...). This is highly likely to fail when run in Karaf. Some examples of this behaviour: * configuring entitlements implementation in brooklyn.properties (or configuring any other class name for that matter) * initializers/enrichers in yaml * objects passed as config keys/sensors to an entity, with the entity not knowing how to load the classes - can't rebind. For example Brooklyn DSL deferred objects / SpecialFlagsTransformer passed as config * PolicyResource trying to attach a policy by class name
Longer term we should introduce bundle knowledge in all of those places. There are various ways to do that - ether by explicitly passing bundle symbolycName + version, loading through a catalog item or another OSGi mechanism altogether. Shorter term I suggest we go for the following workaround, giving us time to introduce proper OSGi behaviour for each of the the above cases: * Pull the class loading logic in a single place. Same as ResourceUtils, but for classes. * Support bundle symbolic name + version embedded in the class name - for example org.apache.brooklyn.policy:0.10.0.SNAPSHOT:org.apache.brooklyn.policy.ha.ServiceFailureDetector. That will allow us to use the existing code paths to pass classes, but be able to resolve them. * Fall back to a white list of bundles to scan for the class name. For example "org.apache.brooklyn.*:0.10.0.SNAPSHOT". This will help in parsing existing yaml plans, using stock enrichers, rebinding. Svet.
