How can I upgrade Eclipse Luna to Mars from Eclipse?

Question

I tried upgrading from Luna to Mars by following the instructions here: https://wiki.eclipse.org/FAQ_How_do_I_upgrade_Eclipse%3F

I added the Mars repository http://download.eclipse.org/releases/mars as an update site and then did check for updates. But I get the exception

An error occurred while collecting items to be installed
session context was:(profile=epp.package.java, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
No repository found containing: osgi.bundle,org.eclipse.epp.package.java,4.5.0.20150603-1639
No repository found containing: binary,epp.package.java.executable.gtk.linux.x86_64,4.5.0.20150603-1639
No repository found containing: org.eclipse.update.feature,org.eclipse.epp.package.common.feature,4.5.0.20150603-1639
No repository found containing: org.eclipse.update.feature,org.eclipse.epp.package.java.feature,4.5.0.20150603-1639

How can I fix this?

Answer 1

Before upgrading I first check the availables web sites for update. I disable all from the previous releases and start by performing an update on the already installed components. After this upgrade I just add

http://download.eclipse.org/releases/mars

and upgrade to the new release of eclipse.

Answer 2

I don’t know how relevant it is but for the record I not only added the mars release update site but also this one: http://download.eclipse.org/eclipse/updates/4.5

Maybe a duplicate? If so, let me know ;)

Answer 3

This is a bad idea. If you upgrade your Eclipse, it will be difficult to fall back when you want to (and you will).

Better is to create a new Eclipse instance and new (set of) workspace(s) for Mars. Then either point to your existing Team repositories or import your existing projects.