Oct 23 2023
The Singleton Pattern Demystified
The Singleton pattern, at its core, guarantees that a class has only one instance and provides a global point of access to that instance. This means that no matter how many times you request an instance of the class, you will always get the same one. Singleton is particularly useful when you need to manage shared resources or control access to a single point, such as a configuration manager, database connection, or, in our case, a logging system.
The Logger Example
Setting Up the Logger
Let's create a simple logger that will maintain a single log throughout the application. Here's our
In this implementation, we've defined a
Logger class that allows logging messages and displaying them. The
getInstance static method ensures that only one instance of the
Logger class exists throughout your application.
Use the Singleton Logger
Now, let's see how we can utilize the Singleton logger in different parts of our application.
app.js (Usage in One File)
app.js, we import the Logger instance, create a
loggerInstance1, and use it to log messages. The beauty of the Singleton pattern is that we are always working with the same instance, ensuring that all logs are stored in one centralized location.
anotherFile.js (Usage in Another File)
anotherFile.js, we again import the same
Logger instance and use
loggerInstance2. Despite being in a different file, loggerInstance2 is essentially the same instance as
loggerInstance1. This means that all logs from both files are accumulated in the same log array, giving you a comprehensive overview of your application's behavior.
Benefits of the Singleton Logger
1 - Centralized Logging: All log messages are collected in one place, making it easier to trace application behavior and debug issues.
2 - Consistency: You can be confident that you're working with the same logger instance throughout your application, ensuring data integrity.
3 - Easy Integration: The Singleton logger seamlessly integrates into different parts of your code, enhancing overall code efficiency.