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Collections in Java

Collections in Java

Introduction to Collections Framework The Collections Framework provides a well defined set of interfaces and classes for storing and manipulating the groups of data into a single unit. Introduction to Collections Framework Collections Framework: The Collections Framework provides a well-designed set of interfaces and classes for storing and manipulating the groups of data into a single unit. The collections framework is a unified architecture which is used to represent and manipulate collections. The framework allows the collections to get manipulated independently, additionally it reduces the programming efforts and increases performance. It includes implementation of interfaces and algorithms. Basically it is a unified architecture that consists the following collections: Interfaces: These are the abstract data types that represent collections. With the help of interfaces we manipulate collections independently. A hierarchy is generally formed with interfaces in object-oriented languages. Implementations: They are the reusable data structures with the concrete implementations of the collection interfaces. Algorithms: Algorithms are used to perform computations, such as searching, sorting etc on the objects that implement collection interfaces. They provide reusable functionality i.e. the same method can be used with different implementations of the collection interfaces. Hence they are also said to be polymorphic. General-purpose Implementations: These are the primary implementations of the collection interfaces. Infrastructure: Interfaces that provide essential support for the collection interfaces. Array Utilities: Utility functions for arrays of primitives and reference objects. This functionality was added to the Java platform as a part of the Collections Framework.

Java Collections:

  1. Interfaces
  2. Iterable
  3. Collection
  4. Generic Collections
  5. List
  6. Set
  7. SortedSet
  8. NavigableSet
  9. Map
  10. SortedMap
  11. NavigableMap
  12. Queue
  13. Deque
  14. Stack
  15. hashCode() and equals()
  16. Sorting

























































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