您已经忘记了
BiFunction：
public static void main(final String[] args) throws Exception { final Map<String, Integer> map = new HashMap<>(); map.put("A", 1); map.put("B", 2); map.put("C", 3); final BiFunction<String, Integer, Integer> remapper = (k, v) -> v == null ? 42 : v + 41; map.compute("A", remapper);}运行：
PS C:UsersBoris> java -versionjava version "1.8.0-ea"Java(TM) SE Runtime Environment (build 1.8.0-ea-b120)Java HotSpot(TM) 64-Bit Server VM (build 25.0-b62, mixed mode)
