The Singleton pattern has several advantages over static classes.
- First, a singleton can extend classes and implement interfaces, while a static class cannot (it can extend classes, but it does not inherit their instance members).
- A singleton allows access to a single created instance – that instance (or rather, a reference to that instance) can be passed as a parameter to other methods, and treated as a normal object. A static class allows only static methods.
- Singleton objects are stored in Heap, but static objects are stored in stack.
- We can clone (if the designer did not disallow it) the singleton object, but we can not clone the static class object .
- Singleton classes follow the OOP (object oriented principles), static classes do not.
- We can implement an
interfacewith a Singleton class, but a class’s static methods (or e.g. a C#
static class) cannot.