If you build an application for the SpringSource dm Server, or any other OSGi platform, you'll probably encounter the uses directive before long. Unless you have a clear understanding of the purpose of the directive, you won't know when to code it and you'll be left guessing when a bundle fails to resolve because of a uses conflict. This article should give you a thorough understanding of the uses directive, when to use it, and how to debug uses conflicts. OSGi is designed so that once bundles are 'resolved', you shouldn't typically hit class cast exceptions and similar problems due to type…

The SpringSource Application Platform is constructed from OSGi bundles and supports applications which are also constructed from OSGi bundles. The Platform supports the standard features of OSGi, but it also supports some additional manifest headers. Several people have asked Why did SpringSource add proprietary headers? and What are the semantics of the new headers?, so this post explains the background motivation and the semantics of Import-Library and Import-Bundle. So OSGi savvy developers can use the Platform as a standard OSGi container and benefit from Platform features such as: For…