what is the use of SingleTon Design pattern?

Question

java,j2ee

Answer 1

Singleton is probably the most widely used design pattern. Its intent is to ensure that a class has only one instance, and to provide a global point of access to it. There are many situations in which a singleton object is necessary: a GUI application must have a single mouse, an active modem needs one and only one telephone line, an operating system can only have one window manager, and a PC is connected to a single keyboard. I will show how to implement the singleton pattern in C++ and explain how you can optimize its design for single-threaded applications.

class Singleton
{
public:
static Singleton* Instance();
protected:
Singleton();
Singleton(const Singleton&);
Singleton& operator= (const Singleton&);
private:
static Singleton* pinstance;
};

n so on n on

Answer 2

Get hold of a book on Design Patterns. for Java I would recommend the book below ( Head first Design Pattern)