What is the chronological order when searching for an element in a HashMap if all objects have the same hash function value?

If all objects in a HashMap have the same hash function value, then they will all fall into one bucket. In this case, the search for an element degrades from amortized O(1) to O(n), where n is the number of elements in that bucket.

Previously, Java HashMap used a linked list to store collisions, which led to linear search time. Starting with Java 8, when a certain threshold of elements in a bucket is reached, the list is transformed into a balanced tree (e.g., red-black tree), which improves search time to O(log n).

Thus, with the same hash:

• In Java before 8: O(n)
• In Java 8 and above: O(log n) after transformation into a tree

This emphasizes the importance of a good hash function for uniform distribution of elements.