SimpleNode[] () { if (myGroups == null || myGroups.isEmpty()) { return NO_CHILDREN; } ArrayList<MyNode> list = new ArrayList<>(); for (ConfigurableGroup group : myGroups) { for (Configurable configurable : group.getConfigurables()) { list.add(new MyNode(this, configurable, 0)); } } return list.toArray(new SimpleNode[0]); }