Bug 15301 'show in packages view' - does not work fo java files not in source folders
20020502 open a java file that is in a resource folder (so it is not an ICompilationUnit - just a file with .java extension) 'show in packages view' is present in the context menu but it does nothing
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/BaseJavaElementContentProvider.java
import org.eclipse.ui.part.FileEditorInput;
 
/**
 * A base content provider for Java elements. It provides access to the
 * Java element hierarchy without listening to changes in the Java model.
 * Use this class when you want to present the Java elements 
 * in a modal dialog or wizard.
 * <p>
 * The following Java element hierarchy is surfaced by this content provider:
 * <p>
 * <pre>
Java model (<code>IJavaModel</code>)
   Java project (<code>IJavaProject</code>)
      package fragment root (<code>IPackageFragmentRoot</code>)
         package fragment (<code>IPackageFragment</code>)
            compilation unit (<code>ICompilationUnit</code>)
            binary class file (<code>IClassFile</code>)
 * </pre>
 * </p> 			
 * <p>
 * Note that when the entire Java project is declared to be package fragment root,
 * the corresponding package fragment root element that normally appears between the
 * Java project and the package fragments is automatically filtered out.
 * </p>
 */
public class BaseJavaElementContentProvider implements ITreeContentProvider {
	protected static final Object[] NO_CHILDREN= new Object[0];
	protected boolean fProvideMembers= false;
	protected boolean fProvideWorkingCopy= false;