Prerequisites

You can also join with List :: addAll, but this time we will join with the following conditions.

--You can enter as many lists as you like --The original list is not affected --Do not do new

manner

You can do this by using the flatMap of the Stream API. If you want to replace it with an array, you can do it with .flatMap (Arrays :: stream).

List l1, l2, l3; //Assuming an initialized list

List merged = Stream.of(l1, l2, l3).flatMap(Collection::stream).collect(Collectors.toList());

[Java] Combine multiple Lists (Collections)

Prerequisites

manner