fElements.remove(workingSet);
    void removeSelectedWorkingSets() {        ISelection selection = listViewer.getSelection();        if (selection instanceof IStructuredSelection) {            IWorkingSetManager manager = WorkbenchPlugin.getDefault()                    .getWorkingSetManager();            Iterator iter = ((IStructuredSelection) selection).iterator();            while (iter.hasNext()) {                IWorkingSet workingSet = (IWorkingSet) iter.next();                if (addedWorkingSets.contains(workingSet)) {                    addedWorkingSets.remove(workingSet);                } else {                    IWorkingSet[] recentWorkingSets = manager                            .getRecentWorkingSets();                    for (int i = 0; i < recentWorkingSets.length; i++) {                        if (workingSet.equals(recentWorkingSets[i])) {                            removedMRUWorkingSets.add(workingSet);                            break;                        }                    }                    removedWorkingSets.add(workingSet);                }                manager.removeWorkingSet(workingSet);            }            listViewer.remove(((IStructuredSelection) selection).toArray());        }    }