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| <h1>Fragments</h1> | |
| <p>A plug-in <b> fragment</b> is used to provide additional plug-in | |
| functionality to an existing plug-in after it has been installed. Fragments are | |
| ideal for shipping features like language or maintenance packs that typically | |
| trail the initial products for a few months. Another frequent use of fragments | |
| is to deliver OS or windowing system-specific features. </p> | |
| <p>When a fragment is detected by the platform and its parent plug-in is found, | |
| the fragment's libraries, extensions and extension points are "merged" with | |
| those of the parent plug-in. </p> | |
| <p>While this merging mechanism is good from a runtime point of view, | |
| developers need to view | |
| fragments as separate entities while working on them. Fragment development is | |
| often done by different teams, on a different schedule, sometimes even on | |
| different operating systems from the original plug-in.</p> | |
| <p>PDE provides full support for fragment development. Fragments can be viewed as | |
| "limited plug-ins". They have all of the capability of regular | |
| plug-ins but have no concept of life-cycle. Fragments have no top-level class | |
| with "startup" and "shutdown" methods.</p> | |
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