class GraphContextMenu {

    private final VizConfig config;
    private final AbstractEngine engine;
    private final DataBridge dataBridge;

    public GraphContextMenu() {
        config = VizController.getInstance().getVizConfig();
        engine = VizController.getInstance().getEngine();
        dataBridge = VizController.getInstance().getDataBridge();
    }

    public JPopupMenu getMenu() {
        GraphContextMenuItem[] items = getGraphContextMenuItems();
        final List<NodeModel> selectedNodeModels = engine.getSelectedNodes();
        Node[] selectedNodes = new Node[selectedNodeModels.size()];
        int i = 0;
        for (NodeModel nm : selectedNodeModels) {
            selectedNodes[i++] = nm.getNode();
        }
        final Graph graph = dataBridge.getGraph();
        JPopupMenu contextMenu = new JPopupMenu();

        //Add items ordered:
        Integer lastItemType = null;
        for (GraphContextMenuItem item : items) {
            item.setup(graph, selectedNodes);
            if (lastItemType == null) {
                lastItemType = item.getType();
            }
            if (lastItemType != item.getType()) {
                contextMenu.addSeparator();
            }
            lastItemType = item.getType();
            if (item.isAvailable()) {
                contextMenu.add(createMenuItemFromGraphContextMenuItem(item, graph, selectedNodes));
            }
        }

        return contextMenu;
    }

    /**
     * <p>
     * Prepares an array with one new instance of every GraphContextMenuItem and
     * returns it.</p>
     * <p>
     * It also returns the items ordered first by type and then by position.</p>
     *
     * @return Array of all GraphContextMenuItem implementations
     */
    public GraphContextMenuItem[] getGraphContextMenuItems() {
        ArrayList<GraphContextMenuItem> items = new ArrayList<>();
        items.addAll(Lookup.getDefault().lookupAll(GraphContextMenuItem.class));
        sortItems(items);
        return items.toArray(new GraphContextMenuItem[0]);
    }

    public JMenuItem createMenuItemFromGraphContextMenuItem(final GraphContextMenuItem item, final Graph graph,
                                                            final Node[] nodes) {<FILL_FUNCTION_BODY>}

    private void sortItems(ArrayList<? extends GraphContextMenuItem> m) {
        Collections.sort(m, new Comparator<GraphContextMenuItem>() {
            @Override
            public int compare(GraphContextMenuItem o1, GraphContextMenuItem o2) {
                //Order by type, position.
                if (o1.getType() == o2.getType()) {
                    return o1.getPosition() - o2.getPosition();
                } else {
                    return o1.getType() - o2.getType();
                }
            }
        });
    }
}

        ContextMenuItemManipulator[] subItems = item.getSubItems();
        if (subItems != null && item.canExecute()) {
            JMenu subMenu = new JMenu();
            subMenu.setText(item.getName());
            if (item.getDescription() != null && !item.getDescription().isEmpty()) {
                subMenu.setToolTipText(item.getDescription());
            }
            subMenu.setIcon(item.getIcon());
            Integer lastItemType = null;
            for (ContextMenuItemManipulator subItem : subItems) {
                ((GraphContextMenuItem) subItem).setup(graph, nodes);
                if (lastItemType == null) {
                    lastItemType = subItem.getType();
                }
                if (lastItemType != subItem.getType()) {
                    subMenu.addSeparator();
                }
                lastItemType = subItem.getType();
                if (subItem.isAvailable()) {
                    subMenu.add(createMenuItemFromGraphContextMenuItem((GraphContextMenuItem) subItem, graph, nodes));
                }
            }
            if (item.getMnemonicKey() != null) {
                subMenu.setMnemonic(item.getMnemonicKey());//Mnemonic for opening a sub menu
            }
            return subMenu;
        } else {
            JMenuItem menuItem = new JMenuItem();
            menuItem.setText(item.getName());
            if (item.getDescription() != null && !item.getDescription().isEmpty()) {
                menuItem.setToolTipText(item.getDescription());
            }
            menuItem.setIcon(item.getIcon());
            if (item.canExecute()) {
                menuItem.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        new Thread() {
                            @Override
                            public void run() {
                                DataLaboratoryHelper.getDefault().executeManipulator(item);
                            }
                        }.start();
                    }
                });
            } else {
                menuItem.setEnabled(false);
            }
            if (item.getMnemonicKey() != null) {
                menuItem.setMnemonic(item.getMnemonicKey());//Mnemonic for executing the action
                menuItem.setAccelerator(KeyStroke.getKeyStroke(item.getMnemonicKey(),
                    KeyEvent.CTRL_DOWN_MASK));//And the same key mnemonic + ctrl for executing the action (and as a help display for the user!).
            }
            return menuItem;
        }
    
<no_super_class>