java maintain insertion order in map

Question

I am initializing a map with a bunch of values. The order of the values is important, and when I do myMap.values(), I'd like them to all come out in the order they went in. What data structure should I be using for that?

Map<String, String> myMap = new SomeKindOfMap<String, String>();
myMap.put(key1, value1)
myMap.put(key2, value2)
//etc

Try [`LinkedHashMap`](https://docs.oracle.com/javase/8/docs/api/java/util/LinkedHashMap.html). — Thomas, May 12 '17 at 15:55

score 3 · Accepted Answer · answered May 12 '17 at 15:56

3

You're looking for a LinkedHashMap. Pro tip: If you go to the JavaDoc for an interface like Map, there's a "All Known Implementing Classes" section where you can see a list of all implementations in the JDK, and see if any meet your needs...

answered May 12 '17 at 15:56

T.J. Crowder

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Upvt: That ProTip may seem trivial but it truly has helped me a lot. – Manish Kumar Sharma May 12 '17 at 15:59
@pulp_fiction: Me too. :-) – T.J. Crowder May 12 '17 at 16:01

java maintain insertion order in map

1 Answers1