How does the sequence of inserting elements into a HashMap structure occur?

In the structure of HashMap, elements are inserted in the following sequence:

1. The hash value of the key is computed using the hashCode() method.
2. The hash value is transformed into an array index (buckets) using an operation, such as taking the remainder by the array size or a bit mask.
3. If the cell in the array (bucket) is empty, a new entry with the key and value is created.
4. If the bucket already contains elements (collision), key comparison is performed using the equals() method:
   • If the key already exists, the value is updated.
   • If the key is new, the element is added to a linked list or a tree (in newer versions of Java HashMap, a tree is used when there are many collisions).

Thus, the insertion sequence depends on the hashing of the key and collision resolution. The order of traversal of elements in HashMap is not guaranteed and does not match the insertion order.