filter Java collection in lambda w/o creating new one

Question

I have a final ConcurrentMap in Java and want to filter it's elements without creating a new one.

Question is: can I reference collection (people) from inside the lambda?

final ConcurrentMap<String, String> people = new ConcurrentHashMap<>();
people.put("Sam", "developer");
people.put("Kate", "tester");

people.forEach((name, role) -> {
    if (name.length() > 3)
        people.remove(name);
});

Answer 1

.keySet(), .values(), and .entrySet() return live views of a map's keys, values and entries respectively. You can remove elements from those collections and the corresponding entries will be removed from the map:

people.keySet().removeIf(name -> name.length() > 3);