The Eclipse runtime itself is factored into several components:
If your plug-in has a dependency on the org.eclipse.core.runtime, then it will continue to run unchanged. However, if you would like to minimize the number of dependencies, then you are able to pick only the runtime bundles that you use.
If you would like to use Import-Package directive (rather than Require-Bundle) then you should be aware that the org.eclipse.core.runtime package is split across several bundles.
To import only the content of this package provided by the org.eclipse.equinox.common bundle, use this line in the manifest file:
Import-Package: org.eclipse.core.runtime; common="split"
To import the content of the package from the org.eclipse.equinox.registry and org.eclipse.equinox.common bundles, use:
Import-Package: org.eclipse.core.runtime; registry="split"
And to import the complete package, use: