Java 的 LinkedHashMap 是否维护键的顺序?

调用LinkedHashMap.keySet()时，返回Set的顺序会和key的添加顺序一致吗?

解决方案

是的.

参见:LinkedHashMap:p><块引用>

这个链表定义了迭代排序，通常是顺序其中钥匙被插入地图(插入顺序).

并来自 HashMap#keySet 文档:

<块引用>

集合 [returned] 由地图支持，所以地图的变化反映在集合，反之亦然.

When LinkedHashMap.keySet() is called, will the order of the Set returned be the same as the order the keys were added in?

解决方案

Yes.

See: LinkedHashMap:

This linked list defines the iteration ordering, which is normally the order in which keys were inserted into the map (insertion-order).

and from the HashMap#keySet documentation:

The set [returned] is backed by the map, so changes to the map are reflected in the set, and vice-versa.