Users of Import-Package: org.eclipse.core.runtime

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If you have a plug-in which uses the
OSGi manifest header Import-Package to access the package org.eclipse.core.runtime
(i.e. Import-Package: org.eclipse.core.runtime) then read on.  Otherwise
you can disregard this note.  Note that most plug-ins in Eclipse use
Require-Bundle instead of Import-Package.  Require-Bundle users can
disregard this note.

During the 3.2 development cycle the
runtime team has been hard at work splitting up the org.eclipse.core.runtime
plug-in into separate plug-ins.  This has resulted in the org.eclipse.core.runtime
package being split across three plug-ins (org.eclipse.equinox.common,
org.eclipse.equinox.registry and org.eclipse.core.runtime).  As a
result if you have a plug-in which simply uses the header "Import-Package:
org.eclipse.core.runtime" then you may get wired to any one of the
three exporters.  

To remedy this the runtime team has
updated the exporters of the split package with a mandatory directive.
  The mandatory directive forces importers to specify which plug-in
they want the package from (using the bundle-symbolic-name matching attribute).
 Bundles which use "Import-Package: org.eclipse.core.runtime"
will now be forced to use the complete package as it is exported from org.eclipse.core.runtime.
 There may be a few unlikely plug-ins out there that were using "Import-Package:
org.eclipse.core.runtime" when only a selected set of the split runtime
plug-ins are installed.  This is not common because it would involve
a platform that did not include the org.eclipse.core.runtime plug-in.  For
example, you may have a platform that only includes the org.eclipse.equinox.common
plug-in.  This plug-in exports a part of the org.eclipse.core.runtime
bundle.  If you have a plug-in that only requires the common part
of the package then you will have to use the following Import-Package header


Import-Package: org.eclipse.core.runtime;
bundle-symbolic-name="org.eclipse.equinox.common"

This specifies that you only want the
part of the org.eclipse.core.runtime package which is exported by the org.eclipse.equinox.common
plug-in.  For more information or to track this issue see https://bugs.eclipse.org/bugs/show_bug.cgi?id=132200

Tom