LoadFactor is 75% if more than that data is reached then memory is doubled
Big O Notation
Retrieval Time – O(1)
HashMap in Java works on hashing principles.
It is a data structure which allows us to store object and retrieve it in constant time O(1) provided we know the key.
In hashing, hash functions are used to link key and value in HashMap.
Objects are stored by calling put(key, value) method of HashMap and retrieved by calling get(key) method.
When we call put method, the hashcode() method of the key object is called so that the hash function of the map can find a bucket location to store value object, which is actually an index of the internal array, known as the table.
HashMap internally stores mapping in the form of Map.Entry object which contains both key and value object.