Javatpoint Logo
Javatpoint Logo

Difference between Map and HashMap

The Map is an interface in Java used to map the key-pair values. It is used to insert, update, remove the elements. Whereas the HashMap is a class of Java collection framework.

The Map interface can only be used with an implementing class. It allows to store the values in key-pair combination; it does not allow duplicate keys; however, we can store the duplicate values. Its implementing classes are as follows:

HashMap is a powerful data structure in Java used to store the key-pair values. It maps a value by its associated key. It allows us to store the null values and null keys. It is a non-synchronized class of Java collection.

Implementation of the Map Interface

The Map interface can be implemented by using the implementing class. Consider the below example:



Implementation of the HashMap Class

HashMap class can be declared as follows:

Consider the below example to implement the HashMap:


Iterating Hashmap...
1 Chris
2 Morris
3 Sam
4 Cruise

Key Differences between Map and HashMap

Some key differences between the Map and HashMap are as follows:

  • The Map is an interface, and HashMap is a class of the Java collection framework.
  • The Map interface can be implemented by using its implementing classes. In comparison, the HashMap class implements the Map interface.
  • The Map contains unique key-pair values. But, the HashMap can hold duplicate values.
  • The Map does not allow null values. But the HashMap can have one null key and multiple values.
  • The Map has two implementations, which are HashMap and TreeMap. Whereas HashMap implements Map interface and extends AbstractMap class.
  • There is no difference between the Map and HashMap objects.

Youtube For Videos Join Our Youtube Channel: Join Now


Help Others, Please Share

facebook twitter pinterest

Learn Latest Tutorials


Trending Technologies

B.Tech / MCA