Collections Overview

Java Collections At A Glance.....mind it !

Collections framework provides a set of standard utility classes and interfaces to handle collections of object.
Collections Framework consists of three parts:

• Core Interface.
• Concrete Implementation.
• Algorithms such as sorting and searching.

mind it....
          collection,represents any of the data structures in which objects are stored and iterated.
          Collection is an interface(java.util.Collection).
          Collections is a class,holds apile of static utility methods.
What do we do with a Collection ?

• Add object to the collection.
• Remove object from the collection.
• Find out if an object(or group of objects) is in the collection.
• Retrieve an object from the collection(without removing it).
• Iterate through the collection,looking at each element one after another.

Interface and class hierarchy for collections

• Lists      Lists of thing(classes that implements List).
• Sets       Unique things(classes that implements Set).
• Maps     Things with a unique ID((classes that implements Map).
• Queues  Things arranged by the order in which they are to be processed.

           More about  ArrayList (Click here) , Vector(Click here).
           More about  Set Interface(Click here).