question: implementation of graphnode interface . concode_field_sep HashSet<DF_Equation> defs concode_elem_sep int index concode_elem_sep HashSet<DF_Equation> uses concode_elem_sep int scratch concode_field_sep void addUse concode_elem_sep void addDef concode_elem_sep Iterator<DF_Equation> getUses concode_elem_sep void setIndex concode_elem_sep int setScratch concode_elem_sep int getScratch concode_elem_sep Iterator<DF_Equation> getDefs concode_elem_sep String toString concode_elem_sep GraphNodeEnumeration inNodes concode_elem_sep GraphNodeEnumeration outNodes
target: int function ( ) { return index ; }