If I have a
List<List<Object>> can I turn it into a
List<Object> that contains all the objects using continuous (not breaking the invocation sequence) invocations of lambdas?
You can use
flatMap to flatten the internal lists (after converting them to Streams) into a single Stream, and then collect the result into a list :
List<List<Object>> list = ... List<Object> flat = list.stream() .flatMap(List::stream) .collect(Collectors.toList());