The only "oneliner" I've found is:
persons.fold(HashMap<Int, String>(), { map, person -> map.put(person.id, person.name); map })
Not so pretty as python's version...
The only "oneliner" I've found is:
persons.fold(HashMap<Int, String>(), { map, person -> map.put(person.id, person.name); map })
Not so pretty as python's version...