Checking whether Components are Managed and Used

Author: Eike Stepper

Publishing Eclipse plug-ins for use by clients involves specifying features to include those plug-ins and then building and publishing or exporting those features. As such, it's expected that every plug-in will be included by some feature. Also, features can include other features, so generally this inclusion structure induces a directed acyclic graph of dependencies of features on other plug-ins and features.

The version manager analyzes the dependency graph and produces an error on each reference to a plug-in or feature that's included in the graph but doesn't specify a Version Management Tool builder with the same release as the referencing feature. The quick fix for the error adds the Version Management Tool builder to the .project of the referenced plug-in or feature.

The version manager also analyzes the dependency graph to determine the roots, i.e., plug-ins or features that are managed but are not referenced by any other feature, and produces an error on the ID in the MANIFEST.MF or feature.xml of each such component. The quick fix for the error adds the project for that plug-in or feature to the Version Management Tool builder's specified properties file's root.projects property. It's clear that each managed release must have at least one root feature and because plug-ins can't generally be released without being included in a feature, a plug-in is generally not expected to be a root component.