#30 Can't install iin Eclipse Oxygen due to missing dependency

[Luke Usherwood]

Szia / Hi! I recently switched to Eclipse Oxygen (M5), and I now get the following error in the "Install new software" dialog when trying to install the ANTLR2 editor:

Cannot complete the install because one or more required items could not be found.
  Software being installed: org.antlr.ui 4.1.4.20141115-0900 (org.antlr.ui.feature.group 4.1.4.20141115-0900)
  Missing requirement: org.antlr.doc 2.7.6.20140601-0730 (org.antlr.doc 2.7.6.20140601-0730) requires 'bundle org.eclipse.core.runtime.compatibility 0.0.0' but it could not be found
  Cannot satisfy dependency:
    From: org.antlr.ui 4.1.4.20141115-0900 (org.antlr.ui.feature.group 4.1.4.20141115-0900)
    To: org.antlr.doc [2.7.6.20140601-0730]

A quick search around found another plugin hit by this issue:

https://bugs.eclipse.org/bugs/show_bug.cgi?id=496871

• see comment:1 therein where they have suggestions for porting off the v2.0 API as the compatability layer has now been removed.

That comment also pointed me towards this (root cause?)...

https://bugs.eclipse.org/bugs/show_bug.cgi?id=394739

... which gave me a hint at a workaround, which surprisingly seems to have worked. I just copied the following 2 items from an Eclipse Mars installation into the eclipse/plugins folder:
* org.eclipse.core.runtime.compatibility_3.2.300.v20150423-0821.jar
* org.eclipse.core.runtime.compatibility.registry_3.6.0.v20150318-1505

(I'm not sure whether the latter is required or not.)

So far so good! I'll try and post an update here if I encounter any problems with this workaround.

[Niko.F]

Just as an update, it worked for me as well, with Eclipse Neon 3 (Eclipse IDE for Java EE). I had to only copy the jar file indicated above (copying the directory was not necessary).