How to preserve insertion order in HashMap?
hashmap, java
Solution
`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.
Problem
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?