SortedMap : Java Glossary

If you have been using a HashMap and discover you also need the pairs in sorted order, you may have disovered the code you need is rather convoluted. Instead use a SortedMap interface e.g. TreeMap which gives you both the Map lookup and the sorted set. TreeMap maintains all the keys in order at all times which usually takes more overhead that sorting the keys once at the end as you would do exporting a HashMap.

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