So your bundle tries to import the com.sun.java.swing package, and when the framework tries to resolve the bundle, it cannot find anybody exporting this package. That is what the error message is trying to tell you.
In Java 7 (I have not checked older versions) this package is part of the JRE. This means the easiest way to expose it to bundles is by having the framework export it as an "extra" package. You can configure a system property when starting your framework to do that:
-Dorg.osgi.framework.system.packages.extra=com.sun.java.swing
The other alternative you have is to embed this package inside your bundle. In that case you don't need to export it via the framework (which is convenient in case you cannot reconfigure your framework) and the import package can be removed from your bundle as well. If you end up having many bundles that need this, this is probably not that convenient or good, as you will end up with many private copies of the package (instead of everybody sharing one).