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I remember my first Java interview. The interviewer asked: "Which collection would you use to store unique user IDs with fast lookup?" I froze. ArrayList? HashMap? HashSet? They all sounded right. And wrong. I mumbled something about ArrayList, added...

Most devs think they understand equals() and hashCode(). They don’t. They override one and forget the other. Furthermore, they assume a working HashMap means a correct one. They let mutability creep into keys. And then act surprised when retrieval fa...

Starting from this post, I'm shifting gears.The next few blogs will be purely technical — heavier, sharper, with no extra storytelling. HashMap looks simple on the surface.But when you go under the hood, especially after Java 8, it’s clear it wasn’t ...

Thread-Safe Collections in Java: ConcurrentHashMap vs Synchronized Collections Thread safety is a crucial consideration when working with collections in multi-threaded Java programs. ConcurrentHashMap and synchronized collections are two of Java's ma...

[60] Java Collection Framework The Java Collection Framework is a set of classes and interfaces in Java that provide commonly reusable, type-safe and efficient data structures to store and manipulate group of objects. The framework consists of severa...
