以相反顺序遍历LinkedHashMap [英] Iterating through a LinkedHashMap in reverse order

问题描述

我有一个LinkedHashMap：

I have a LinkedHashMap:

LinkedHashMap<String, RecordItemElement>

，我需要从给定键的位置向后迭代。因此，如果我获得了第10项的关键字，则需要通过hashmap 9,8,7等向后迭代。

that I need to iterate through from a given key's position, backwards. So if I was given the 10th item's key, I'd need iterate backwards through the hashmap 9, 8, 7 etc.

推荐答案

你不必遍历它。但是，将键关闭并将其存储在列表中将会很方便。这是您可以执行indexOf（）类型操作的唯一方法。

You don't have to iterate through it. But it would be handy to pull the keys off and store it in a list. Thats the only way you can do indexOf() type operations.

List<String> keyList = new ArrayList<String>(map.keySet());
// Given 10th element's key
String key = "aKey";
int idx = keyList.indexOf(key);
for ( int i = idx ; i >= 0 ; i-- ) 
 System.out.println(map.get(keyList.get(i)));

这篇关于以相反顺序遍历LinkedHashMap的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！