仅存储最近n个条目的字典或类似数据结构？

Question

I'm wondering if there's a built-in Java data structure that behaves like a dictionary but only keeps a fixed number of recent entries. So I could keep the size more-or-less constant but also have it behave like a dictionary or hashmap.

Answer 1

You could create one quite easily by extending LinkedHashMap. When adding an entry, check the size and remove the oldest item if already at maximum size.

Answer 2

我认为LRUMap将适合您的需求。