Why LinkedList as a bucket implementation for HashMap?

Question

I understand the workings of HashMap -collisions and everything - trying to understand the deeper mechanics and the choice for entry bucket - and not say an Array (making it a 2 dimensional matrix )? Since search through both are O(n) operations ? I assumed one factor that might make the choice for Linked List is the insertions o(1) factor! Is that a correct assumption?

Answer 1

If it is in Java then the linked list is the bucket. And each entry in the table is a linked list containing the array of entry elements. In that each node knows what is in the next to the list till the time you reach to the end when the next reference is null.

Also do check:-

How does Java's Hashmap work internally?

An array has a predetermined size. So if you use an array, then the hash table has a predetermined size for each of the array elements. Every possible bucket is allocated, and your hash table will become big. This will be make sense if you have very huge memory but if not then use link list and walk through the list to find the match.