public static < E > List < E > concatView ( List < List < ? extends E > > lists ) { if ( lists . isEmpty ( ) ) { return Collections . emptyList ( ) ; } else { return ConcatView . create ( lists ) ; } }
Returns a list that is a concatenation of the given lists . The returned list is a view of the underlying lists without copying the elements . The returned list is unmodifiable . Modifications to underlying lists will be visible through the concatenation view .