What are the Core collection interfaces

Java Collection framework provides interfaces and class implementations that enable data handling simple and meaningful. The Collection Interface resides at the top of the Hierarchy, although Java does not provides a direct implementation of Collection framework but Collection Interface is being implemented by List and Set Classes. The following list describes the core collection interfaces:
  1. Collection - Collection is the root of the collection hierarchy.

  2. List — The List interface extends the Collection interface to maintain a sequence of elements that need not be unique.

  3. Set — The Set interface extends the Collection interface and contains a set of unique elements.

  4. SortedSet — The SortedSet interface extends the Set interface to provide the required functionality for maintaining a set in which the elements are stored in some sorted order.

  5. Queue — A collection used to hold multiple elements prior to processing.

  6. Deque — a collection used to hold multiple elements prior to processing. Besides basic Collection operations, a Deque provides additional insertion, extraction, and inspection operations

  7. Map — an object that maps keys to values.

  8. SortedMap : Extends the Map interface for maps that maintain their mappings sorted in key order.

Java collections framework

Java Collections are predefined set of classes or data structures which can be used to store multiple items in a single unit. Dynamically allocated data structures in Java (such as Hashtable, HashSet, HashMap,LinkedList, Vector, Stack, ArrayList) are supported in a unified architecture called the Collection Framework , which mandates the common behaviours of all the classes. More about... collections framework