/guava/guava/src/com/google/common/collect/Lists.java
backingList.add( index, second) ;
backingList.add ( index, element ) ;
final List<E> backingList; AbstractListWrapper(List<E> backingList) { this.backingList = checkNotNull(backingList); } @Override public void add(int index, @ParametricNullness E element) { <extra_id_0> } @Override public boolean addAll(int index, Collection<? extends E> c) { return backingList.addAll(index, c); } @Override