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Sorting a hash map

I need to sort the hashmap according to the key. The key is a string (so I need to sort it alphabetically) and the value is an integer. I tried searching on the internet and found that the tree set will automatically sort it as soon as you put it in. Can anyone guide me in the right direction as to how I could convert it to a set of trees, or maybe even if I could just sort it with a hashmap.

Thank you in advance

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Since hashmaps are unsorted maps by definition, you will need to use a different container for this. There are several options depending on your needs, some of which are:



  • Use TreeMap

    instead, HashMap

    either temporarily or as a replacement. This would be the best option if you haven't saved the hashmap.
  • Use TreeSet

    to sort the keys and then iterate over the keys and extract the values ​​from HashMap

    .
  • Do the same as option 2, but fill in a new one LinkedHashMap

    during iteration. This will render a map that returns values ​​in insertion order, which happen to be sorted due to the use of a sorted set. Note that adding items to LinkedHashMap

    will add all new items to the end - LinkedHashMap

    still ordered by insertion order.
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