Programatically installing an Eclipse plugin from within Eclipse?

Question

I want to create an automated installer for an Eclipse plugin (i.e. not through the "Update Manager"). My scenario is simple: the user closes Eclipse, drops a downloaded JAR into the dropins folder, starts Eclipse and the rest of the process is automated.

In older Eclipse versions, before the era of P2, Eclipse had (still has) a class called InstallCommand which could be used to install pluings into the currently running platform.

While this still works in Eclipse 3.4 & 3.5, it is not behaving properly: most noticeably, plugins installed that way cannot be automatically uninstalled (it is dimmed).

The JavaDoc claims the InstallCommand is deprecated and should be replaced by a P2 alternative. However, I couldn't find the right tool for the job. There is the P2 director, but it is built for running as a separate application from the command line. It is possible to invoke it from within Eclipse but it is really not cut out for that. For example, progress monitoring and error reporting are not working well.

Does anybody know of a good alternative for that?

Thanks, Zviki

Answer 1

I suggest to deploy your plugin as an executable JAR. The installer in the JAR should ask for the Eclipse install directory and unpack the plugin in the right place (plus some more checks as needed).

Optionally include a little "watchdog" plugin which doesn't depend on much and just checks that your main plugin loads correctly and displays a useful error message which the user can email to you for support.

Answer 2

Dropins seems very close to what you want, especially if they are just downloading jars without the associated metadata (ie the metadata will need to be auto-generated).

You could consider defining a second dropins area to manage yourself. Take a look at ProfileSynchronizer in org.eclipse.equinox.p2.reconciler.dropins, in particular the method createProfileChangeRequest. I expect the uninstall behaviour you don't like is a result of the IInstallableUnit.PROP_PROFILE_LOCKED_IU property being added.

The dropins are reconciled at startup, see the p2.reconciler.dropins Activator.watchDropins(), you can likely do the same from your own bundle to watch another folder.