src/main/java/org/efaps/ui/wicket/models/objects/UIStructurBrowser.java
protected boolean checkForAllowChildren(final Instance _instance)
    {
        setExecutionStatus(UIStructurBrowser.ExecutionStatus.ALLOWSCHILDREN);
        try {
            final List<Return> ret = getObject4Event().executeEvents(EventType.UI_TABLE_EVALUATE,
                            ParameterValues.INSTANCE, _instance,
                            ParameterValues.CLASS, this);
            return ret.isEmpty() ? false : ret.get(0).get(ReturnValues.TRUE) != null;
        } catch (final EFapsException e) {
            throw new RestartResponseException(new ErrorPage(e));
        }
    }
protected boolean checkForAllowChildren(final Instance _instance)
    {
        setExecutionStatus(UIStructurBrowser.ExecutionStatus.ALLOWSCHILDREN);
        try {
            final List<Return> ret = getObject4Event().executeEvents(EventType.UI_TABLE_EVALUATE,
                            ParameterValues.INSTANCE, _instance,
                            ParameterValues.CLASS, this);
            return ret.isEmpty() ? false : ret.get(0).get(ReturnValues.TRUE) != null;
        } catch (final EFapsException e) {
            throw new RestartResponseException(new ErrorPage(e));
        }
    }
This method is used to check if a node has potential children.

@param _instance Instance of a Node to be checked
@return true if this Node has children, else false