Bundle 'org.eclipse.core.runtime' cannot be resolved

Question

I recently upgraded from Eclipse Kepler to Luna. A plugin I had been working on is now showing build errors without any source being changed.

Here is an extract from my MANIFEST.MF,

Require-Bundle: org.eclipse.core.runtime;bundle-version="3.7.0",
 org.eclipse.ui;bundle-version="3.7.0",
 org.eclipse.ui.ide;bundle-version="3.7.0",
 org.eclipse.core.resources;bundle-version="3.7.0",
 org.eclipse.ui.forms;bundle-version="3.6.0",
 org.eclipse.wst.sse.ui;bundle-version="1.3.0",
 org.eclipse.jface.text;bundle-version="3.8.100",
 org.eclipse.ui.workbench.texteditor;bundle-version="3.8.101",
 org.eclipse.ui.views;bundle-version="3.6.0"

None of the core or ui bundles are resolved. I don't think Eclipse could even run without them and their equivalent .jar files are present and readable and haven't been modified as part of the upgrade, so they are not actually missing. When I try to add dependencies on the Dependencies tab the problem bundles do not show.

Eclipse was upgraded by the Arch Linux package manager. I mention it for completeness but believe it is likely identical to any other upgrade mechanism. I also tried creating a new plug-in project but the same happens, I guess this means it's a global setting. I'm relatively new to PDE and so far haven't had a need to change any settings.

Flack

What do you have in Preferences > Plug-in Development > Target Platform? – Yepez

If there are build errors, you need to tell us what they are. – Trimolecular

@Yepez there is only one entry and that is "Running Platform (Active)". – Flack

Apologies @nitind, the question title is the error. I hoped anyone who had seen it before would recognise it and know the fix. – Flack

Tried removing the Running Platform target definition, Applying, and then Restoring Defaults? Maybe it's just stale. – Trimolecular

@Trimolecular please add that as an answer ;-) – Flack

Answer 1

From the preference page (Preferences > Plug-in Development > Target Platform), try Removing the Running Platform target definition, Applying, and then Restoring Defaults. Maybe it's just stale and pointing to the jars that it doesn't know Arch has changed about.

Trimolecular

This worked. I recall immediately after the upgrade there was a message about the workspace being updated in a one-way process. It is possible this introduced too many changes to remain stable. If more problems arise I think I shall rebuild the workspace entirely. – Flack

Same here... I will miss that "11250 errors" message. – Garrot

Worked for me even though my unresolved bundle was from Xtext and not a core one. – Purity

worked for me too, this resolved all bundle errors (eclipse and specific bundles) – Isia

This solution didn't work for me. I have unresolved bundles while the jar files are included into the build path. Does anybody has an idea why ? – Rooftop

@Rooftop Do you have exactly the same steps to reproduce? If not, please open your own question with them. – Trimolecular

@Trimolecular Actually I resolved the problem in another way. I added my bundles to a dropins folder in the Eclipse install and removed them from the build path. – Rooftop

For me nitind's solution didn't work, but it came close. In addition to restoring the Runtime Plaform to defaults (as described in his answer) I had to click Reload... and then close the preferences window with OK. – Underwater

You just saved my weekend mood. Thanks :) – Shemeka