INSTALLATION.md: Eclipse instructions.

docs/INSTALLATION.md

 
 6. Back in the "Default Project Structure" dialog, in the "Project language level:" section,
    select "8 - Lambdas, type annotations etc.".  Click "OK".
+
+## How work with Exercism using Eclipse
+
+This is not a guide about how to learn to use Eclipse. Please, consult
+your favorite search engine for that because there are plenty of tutorials
+already available.
+
+Once you've got Eclipse installed and running, there are at least two ways
+to get exercism tasks into Eclipse: Letting gradle build Eclipse workspace
+for you and using Buildship Gradle plugin for Eclipse. 
+
+Firstly, a simpler way of doing things.
+
+1. Fetch an exercise: `exercism fetch java <exercise>`
+   (see [the list of available exercises](http://exercism.io/languages/java)).
+
+2. Change to the directory containing the exercise: `cd ~/exercism/java/
+   <exercise>` (by default things will end up in `~/exercism`).
+
+3. Let Gradle prepare things for Eclipse: gradle eclipse.
+
+4. Start Eclipse.
+
+5. From the "File" menu select "Import".
+
+6. Select "Existing Projects Into Workspace" as import source.
+
+7. Browse the directory containing the exercise fetched during the
+   step 1 to "Select root directory:".
+
+8. Hit the button labeled "Finish".
+
+Secondly, a slightly more difficult, but more "Eclipseish" way of
+doing things. This is for those who absolutely despise doing anything
+away from Eclipse.
+
+1. Install "Buildship Gradle Integration plugin from Eclipse
+   Marketplace (accessible from Help-menu, under Eclipse Marketplace).
+
+   In case you've been reading about the Gradle STS plugin, note that
+   The Buildship Gradle Integration plugin replaces the Gradle STS plugin
+   which is no longer maintained.
+
+   Start (or restart) Eclipse after the plugin has been installed.
+
+2. Fetch an exercise: `exercism fetch java <exercise>`
+   (see [the list of available exercises](http://exercism.io/languages/java)).
+
+3. From the "File" menu select "Import".
+
+5. Select "Gradle" > "Gradle Project" as your import source.
+
+6. Browse the directory containing the exercise fetched during
+   the step 1 to the "Project root directory:".
+
+7. Hit the button labeled "Finish".
+
+To me it seems that the simple way of doing things is, as usual, the better
+way of doing things. The only caveat I've found this far is that you have
+to run `gradle eclipse` every time you change something affecting Eclipse.
+
+For most exercises there is no need to ever touch build.gradle or anything
+else besides the source files, so this looks like a minor hassle not often
+encountered.