How to preserve insertion order in HashMap?

java hashmap
realtebo picture realtebo · May 22, 2012 · Viewed 361.3k times · Source

I'm using a HashMap. When I iterate over the map, the data is returned in (often the same) random order. But the data was inserted in a specific order, and I need to preserve the insertion order. How can I do this?

Answer

NPE picture NPE · May 22, 2012

LinkedHashMap is precisely what you're looking for.

It is exactly like HashMap, except that when you iterate over it, it presents the items in the insertion order.

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