[news.eclipse.tools] Re: publishing extension points - help!

[Judah Diament <djudah@xxxxxxxxxx>]

Thanks!

Vlad Klicnik wrote:

> Extension points can only be defined ("created") through the plugin.xml. The plugin registry
> is constructed by the platform runtime based on the declarations contained in the various
> plugins. The Java API only provides methods to access this information (r/o).
>
> Judah Diament wrote:
>
> > Vlad,
> >
> > That is very usefull, but it doesn;t really answer my question. I saw in the API docs how
> > to access the registry to see what plugind are around for a given extension point. What I
> > didn;t see is how to CREATE a new extension point. That is, are extnesion points ONLY
> > declared in plugin.xml, or do you also have to do some java to create a new extension
> > point?
> >
> > Thanks,
> > Judah
> >
> > Vlad Klicnik wrote:
> >
> > > Judah, the way you do this is by calling APIs in the
> > > org.eclipse.core.runtime package. In particular, the following are useful
> > >
> > > Platform.getPluginRegistry()
> > > IPluginRegistry.getXXX ... various calls to get descriptors for plugins,
> > > extension points, extensions, etc
> > > methods on IPluginDescriptor, IExtension, IExtensionPoint,
> > > IConfigurationElement
> > >
> > > So to find out which items were configured into your extension point
> > > "com.xyz.myplugin.foopoint" by some other plugin extensions you could do
> > >
> > > IConfigurationElement[] cfg;
> > > cfg =
> > > Platform.getPluginRegistry().getConfigurationElementsFor("com.xyz.myplugin.foopoint");
> > >
> > > To actually interact with one of the extensions (eg. with the first one in
> > > the list returned above) you could then call
> > >
> > > IFoo someFoo = (IFoo) cfg[0].createExecutableExtension("fooclass");
> > >
> > > and once you have your object you are off to the races (see the javadoc for
> > > explanation of the arguments). The idea is that others have plugged in
> > > extensions that define classes implementing your IFoo interface (required by
> > > the extension point) so you actually know how to interact with the resulting
> > > object.
> > >
> > > Also, see Help> Help Contents and select Platform Plug-In Developer Guide
> > > from the drop box.
> > >
> > > Hope this helps you get going.