Difference between HashMap and Map in Java..?

Question

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Java - HashMap vs Map objects

I want to know the difference between HashMap and Map in java..??

Solution 1

Map is an interface, i.e. an abstract "thing" that defines how something can be used. HashMap is an implementation of that interface.

Solution 2

Map<K,V> is an interface, HashMap<K,V> is a class that implements Map.

you can do

Map<Key,Value> map = new HashMap<Key,Value>();

Here you have a link to the documentation of each one: Map, HashMap.

Solution 3

Map is an interface; HashMap is a particular implementation of that interface.

HashMap uses a collection of hashed key values to do its lookup. TreeMap will use a red-black tree as its underlying data store.

Solution 4

Map is an interface in Java. And HashMap is an implementation of that interface (i.e. provides all of the methods specified in the interface).

Solution 5

HashMap is an implementation of Map. Map is just an interface for any type of map.

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