A fragment project is always defined for a host project. At runtime the fragment project is merged with its host project and for the runtime both projects are just one.

Fragment project are always optional for their host plug-in.

To create a fragment project select File → New → Other... → Plug-in Development → Fragment Project.

Fragment project are typical used for containing the tests. This way the tests can access the host plug-in classes, even if the host plug-in does not define them as external API. Sometimes tests are also contained in normal plug-ins, in this case they can only test the external API for other plug-ins.

Another typical usage examples for fragment projects are translations and native code. A new translation can be contributed to a plug-in via a fragment project. SWT makes use of fragment projects to factor out it native code parts.

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