What is the correct way of ensuring a single instance of a class?
131321
What is the correct way to write a singleton pattern in Ruby?
99307
How can I safely (and easily) count *all* instances of a class within my program?
73217
Is there a way to instantiate a class without calling __init__?
93211
When several classes need to access the same data, where should the data be declared?
72062
Is it possible to prevent stack allocation of an object and only allow it to be instantiated with 'new'?
79142
Are static class instances unique to a request or a server in ASP.NET?
124515
Java: Non-static nested classes and instance.super()
13791
What's the best way to ensure a base class's static constructor is called?
111570
What is the difference between class and instance methods?
119077
Singleton: How should it be used
44606
How to properly implement ARC compatible and `alloc init` safe Singleton class?
57541
How to ensure only a single instance of my application runs?
13936
What is the difference between class and instance attributes?
90035
Creating the instance of abstract class or anonymous class
99871
Is a Named Instance more Secure than the Default Instance?
141743
What is the best way to conditionally apply a class?
132039
how to set compile time validation on class instance members