boolean (Collection<? extends ExternalSystemNode<?>> externalSystemNodes, boolean silently) { if (externalSystemNodes.isEmpty()) return false; for (ExternalSystemNode<?> externalSystemNode : externalSystemNodes) { externalSystemNode.setParent(null); if (myChildrenList != NO_CHILDREN_LIST) myChildrenList.remove(externalSystemNode); } if (!silently) { childrenChanged(); } return true; }