question: public void addSubTree ( int index , List < Node > children ) { List < NodeDescriptor > nodeDescriptors = convertTreeNodesHelper ( children ) ; roots . addChildren ( index , nodeDescriptors ) ; List < Node > nodes = new ArrayList < > ( ) ; for ( NodeDescriptor child : nodeDescriptors ) { nodes . add ( child . getNode ( ) ) ; } if ( ! nodes . isEmpty ( ) ) { fireEvent ( new StoreAddEvent ( index , nodes ) ) ; } }
target:  Imports a list of subtrees at the given position in the root of the tree.