nl: lock the chain so no more iterators can be added . this must be called from all iterator interface methods . concode_field_sep Iterator lastUsedIterator concode_elem_sep boolean isLocked concode_elem_sep Iterator currentIterator concode_elem_sep List iteratorChain concode_elem_sep int currentIteratorIndex concode_field_sep Object next concode_elem_sep void checkLocked concode_elem_sep int size concode_elem_sep void addIterator concode_elem_sep boolean isLocked concode_elem_sep boolean hasNext concode_elem_sep List getIterators concode_elem_sep void setIterator concode_elem_sep void updateCurrentIterator concode_elem_sep void remove
code: void function ( ) { if ( isLocked == false ) { isLocked = true ; } }