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Merge lists with stream API

I have the following situation

Map<Key, ListContainer> map; 

public class ListContainer {
  List<AClass> lst;

I have to merge all the lists lst from the ListContainer objects from a Map map.

public static void main(String[] args) {
   List<AClass> alltheObjectsAClass = map.values().stream(). // continue....    

Any idea how, using Java 8 stream API?



I think flatMap() is what you’re looking for.

For example:

 List<AClass> allTheObjects = map.values()
         .flatMap(listContainer ->
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