OSGi is not supported directly by the UIMA™ framework; the framework has no knowledge or interfaces for making use of it. However, components are being packaged as OSGi bundles: in particular, there are Eclipse Plugin tools that are packaged this way. The Eclipse plugins are organized further using the Eclipse infrastructure for Features and Update Sites.

The addon annotators are being packaged experimentally as OSGi bundles. Due to UIMA not knowing about OSGi, the current experimental packaging includes the uimaj-core jar in the package; the expected use of this bundle is as an embedded UIMA "application", running just the one annotator that is being bundled (because other annotators in other bundles will not be "visible" in the class-loading sense).

Users wanting to develop more advance deployments, such as UIMA pipelines containing multiple annotators, can use these bundles and the maven processes that build them, as examples. They will need to create special bundles of their own, combining the UIMA framework and all of the jars for the multiple annotators (and their dependencies) into one bundle. This would then be used as a UIMA application.

OSGi and Eclipse-Buddy

There are two kinds of OSGi container/frameworks. One, represented by Apache Felix, might be characterized as a "pure" OSGi implementation. The other, represented by Eclipse RCP and the equinox framework, is charactereized by including support to enable "legacy" frameworks (including UIMA) be used in some circumstances, by exploiting Eclipse-buddy manifest directives. If users decide to use an OSGi container that supports the Eclipse-buddy directive, then it is possible to create bundle structures where the annotators do not contain uimaj-core jars, and a common uimaj-ep-runtime bundle contains the common UIMA framework jars used by the application. To do this, each annotator bundle will need to have the directive in the MANIFEST.MF Eclipse-RegisterBuddy: org.apache.uima.runtime; furthermore, the bundle uimaj-ep-runtime (having the symbolic name org.apache.uima.runtime) must be the bundle in the container that will provide the UIMA framework. Currently, the experimental OSGi builds do not provide this directive. Apache Felix has stated that they do not support these "buddy" extensions, as a matter of principle.