Implementing the singleton pattern in Java

Question

Can anyone provide an example of a singleton pattern and explain why they are necessary?

Answer 1

Basically, in Java you implement singleton by giving a class a private no-args constructor (private MyClass()), and statically (or lazily) initializing a single instance of the class which is returned by a static MyClass getInstance() method.

You would use this when you want there to be no more than a single instance of your class throughout the entire application.