Mastering Design Patterns with Examples — Singleton Pattern

It can easily go wrong than you might think of

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Overview

Singleton Pattern has the simplest structure among all the design patterns, but it isn’t easy to implement it correctly.

The Singleton Pattern is a popular design pattern that ensures a class has only one instance and provides a global point of access to that instance. It is particularly useful when you need to manage a shared resource or control access to a unique object in your application. In this article, we will dive deep into the Singleton Pattern in Java, discussing its key concepts, various implementations, and potential pitfalls.

Let’s take a look at the definition and key concepts of the Singleton Pattern.

The Singleton Pattern ensures a class has only one instance, and provides a global point of access to it.

1. Ensure a single instance: The class should have only one instance. This is achieved by making the class’s constructor private so that it cannot be instantiated from outside the class.
2. Provide a global point of access: The class should provide a static method (usually called getInstance()) that returns the unique instance of the class. This method checks if the instance already exists…