Map<String, Set<T> > to List in Java 8 -


so have class :

 class user {     public string name;     public integer age;      public user(string name, integer age) {         this.name = name;         this.age = age;     } }

and map:

 map<string, set<integer>> map = new hashmap<>();  map.put("user", set.of(18, 19, 20, 21));

i want obtain list of 4 users here:

  1. name : "john" , age : 18
  2. name : "john" , age : 19
  3. ....
  4. ....

any ideas how can streams in java 8 ?

list<user> users = map.entryset()    .stream()    .flatmap(e -> e.getvalue().stream().map(x -> new user(e.getkey(), x)))    .collect(collectors.tolist());

set.of java-9 btw


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