Question

I research a position of my key in hashMap.
Example :

    HashMap<Integer, String> ht = new HashMap();
    ht.put(1, "c");
    ht.put(10, "b");
    ht.put(8, "r");

    System.out.println(ht);

10 has position 3 in HashMap, 8 has position 2 …

So I have two questions :

1. how to retreive these positions from HashMap?
2. When i have a much element, i use hashMap to retreive a positions or Binary Search ?

Answer 1

HashMap is not a sorted or ordered Map implementation, so there isn’t a “position” here.

LinkedHashMap is an ordered one, TreeMap is a sorted one.