Difference Between Collection Interfaces and Classes in Java

    Difference Between Collection Interfaces and Classes in  Java  

Interface / Class	Description	Type	Allows Duplicates?	Allows Null Values?	Ordering Guaranteed?	Thread-safe?
Collection	The root interface of all collection classes.	Interface	Yes	Yes	No	No
List	A collection that allows duplicate elements and maintains their order.	Interface	Yes	Yes	Yes	No
Set	A collection that does not allow duplicate elements.	Interface	No	Yes	No	No
SortedSet	A Set that maintains its elements in ascending order.	Interface	No	Yes	Yes	No
Navigable Set	A SortedSet with navigation methods.	Interface	No	Yes	Yes	No
Queue	A collection for holding elements that are waiting to be processed.	Interface	Yes	Yes	Yes	No
Deque	A Queue that supports operations at both ends.	Interface	Yes	Yes	Yes	No
Map	An object that maps keys to values.	Interface	No (keys are unique)	Yes (values can be duplicated)	No	No
Sorted Map	A Map that maintains its entries in ascending order of the keys.	Interface	No (keys are unique)	Yes (values can be duplicated)	Yes	No
Navigable Map	A Sorted Map with navigation methods.	Interface	No (keys are unique)	Yes (values can be duplicated)	Yes	No
ArrayList	An implementation of the List interface using an array.	Class	Yes	Yes	Yes	No
LinkedList	An implementation of the List interface using a doubly-linked list.	Class	Yes	Yes	Yes	No
HashSet	An implementation of the Set interface using a hash table.	Class	No	Yes	No	No
Linked Hash Set	An implementation of the Set interface using a hash table with a linked list.	Class	No	Yes	Yes	No
Tree Set	An implementation of the SortedSet interface using a tree.	Class	No	Yes	Yes	No
Array Deque	An implementation of the Deque interface using an array.	Class	Yes	Yes	Yes	No
Priority Queue	An implementation of the Queue interface using a priority heap.	Class	Yes	Yes	Yes	No
HashMap	An implementation of the Map interface using a hash table.	Class	No (keys are unique)	Yes (values can be duplicated)	No	No
Linked HashMap	An implementation of the Map interface using a hash table with a linked list.	Class	No (keys are unique)	Yes (values can be duplicated)	Yes	No
Tree Map	An implementation of the Sorted Map interface using a tree.	Class	No (keys are unique)	Yes (values can be duplicated)	Yes	No