How to get submap of LinkedHashMap by element index?

Question

I am trying to get a submap of LinkedHashMap based on element index. Am I reinventing the wheel here? Sounds like this should be somewhere in API already:

public <K,V> LinkedHashMap<K,V> subMap(LinkedHashMap<K,V> map, int fromIndex, int toIndex) { LinkedHashMap<K,V> result = new LinkedHashMap<K,V>(); int i=0; for(Map.Entry<K,V> entry : map.entrySet()) { if(i >= fromIndex && i < toIndex) { result.put(entry.getKey(), entry.getValue()); } i++; } return result; }

Is this the way to go or there are some other better/existing solutions (within Java 6 API).

How will the returned Map be used? Can you use an iterator instead? If so, you could return a custom iterator that returns values (or Map.Entries) between the specified index range. Keep in mind concurrency issues when dealing with index ranges of a collection. — Nate
– Nate, Commented May 14, 2012 at 18:59

gus · Accepted Answer · 2012-05-14 18:48:21Z

NavigableMap allows you to get a sub-map back, but it requires that you specify a 'from key' and a 'to key', so you can't do it purely on index.

I'm not aware of any other way of doing this via the standard API.

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