Singleton Design Pattern in Java: Thread-Safe, Lazy & Serialization-Proof | Design Patterns Part 1

Is your Singleton really a Singleton? In this video we build the Singleton Design Pattern in Java step by step, from a naive version to a production-ready one, and see how threads and serialization can quietly break it. This is Part 1 of our Design Patterns series (Creational Patterns), made for Java developers and anyone preparing for Low-Level Design (LLD) and system design interviews. What you'll learn: What the Singleton pattern is: one class, one object, one global access point The 3 building blocks: private constructor, static instance, public static getInstance() Lazy initialization and why the basic version is not thread-safe Making it thread-safe with synchronized and double-checked locking (volatile) How serialization can break your Singleton, and how to fix it with readResolve() Real examples: a DBConfig class and an InventoryManager When to use a Singleton, and when to avoid it (hidden global state, harder testing) 📖 Read the full Singleton guide with diagrams and code: https://appkodersolutions.com/low-lev... 💻 Get the complete source code on GitHub: https://github.com/appkodersolution/a... 🔔 Subscribe for more Design Patterns, Low-Level Design and System Design videos, and turn on notifications so you don't miss Part 2. 👍 If this helped, like the video and share it with a friend preparing for interviews. Drop your questions in the comments! #SingletonPattern #DesignPatterns #Java #LowLevelDesign #SystemDesign TAGS singleton design pattern, singleton pattern java, design patterns in java, creational design patterns, thread safe singleton, double checked locking, singleton serialization, readResolve singleton, lazy initialization java, low level design, LLD interview, java interview questions, system design, appkoder solutions