Latest posts
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Singleton Pattern in Java: Ensuring a Single Instance
The Problem Sometimes you need exactly one instance of a class across your whole application — a configuration manager, a connection pool, a logger. The Singleton pattern guarantees a class has only one instance and provides a global point of access to it. Diagram Java Example (thread-safe, lazy) The classic double-checked locking is safe in modern Java because of the volatile keyword, but in real…
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Design Patterns in Java: A Practical Introduction
What Are Design Patterns? A design pattern is a reusable, proven solution to a recurring design problem — not a finished piece of code you copy-paste, but a template for how to structure classes and objects to solve a specific kind of problem. The idea was popularized by the “Gang of Four” (Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides) in their 1994 book Design…