Bug 7914 Cannot copy a Java project in the packages view
There is no way to copy a Java project in the packages view. You can copy a project in the Navigator. This is a functional gap.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/reorg/ReorgDestinationAction.java
for (Iterator iter= editorParts.iterator(); iter.hasNext(); ){
			IEditorPart each= (IEditorPart)iter.next();
			IEditorInput input= each.getEditorInput();
			if (input instanceof IFileEditorInput)
				result.add(((IFileEditorInput)input).getFile());
		}
		return (IFile[]) result.toArray(new IFile[result.size()]);
	}
	private static IRunnableWithProgress createSaveEditorOperation(final Object[] elementsToSave, final List elements, final List unsavedEditors) {
		return new IRunnableWithProgress() {
			public void run(IProgressMonitor pm) {
				pm.beginTask(ReorgMessages.getString("ReorgAction.task.saving"), elementsToSave.length); 
				for (int i= 0; i < elementsToSave.length; i++) {
					IEditorPart editor= (IEditorPart)unsavedEditors.get(elements.indexOf(elementsToSave[i]));
					editor.doSave(new SubProgressMonitor(pm, 1));
				}
				pm.done();
			}
		};
	}
	private static ListSelectionDialog createUnsavedEditorDialog(List unsavedElements) {
		int labelFlags= JavaElementLabelProvider.SHOW_DEFAULT | JavaElementLabelProvider.SHOW_POST_QUALIFIED;
		Shell parent= JavaPlugin.getActiveWorkbenchShell();
		String msg= ReorgMessages.getString("ReorgAction.checkSaveTargets"); 
		ListSelectionDialog dialog= new ListSelectionDialog(parent, unsavedElements, new ListContentProvider(), 
			new JavaElementLabelProvider(labelFlags), msg);
		dialog.setInitialSelections(unsavedElements.toArray());
		return dialog;
	}