How to do .collect() in lambda expression?

Question

Java

NavigableMap<Integer, Items>  filter_result = map.entrySet().stream()
                .filter( item -> item.getValue() < max)
                .limit(size)
                .collect(<???>);

How to get a NavigableMap as an output, given that Items is a custom type, and map is also a NavigableMap?

Answer 1

Collector.of(
    TreeMap::new,
    (map, e) -> map.put(e.getKey, e.getValue()),
    (left, right) -> {left.putAll(right); return left;}
    EnumSet.of(Collector.Characteristics.UNORDERED, Collector.Characteristics.IDENTITY_FINISH))

something like this.
You can also write your own Collector.
But it can be simpler like this:

NavigableMap<Integer, Items> result = new TreeMap<>();

...forEach(e -> result.put(e.getKey(), e.getValue())