Boxed In: A Beginner's Guide to Autoboxing and Unboxing in Java

A beginner-to-intermediate tutorial explaining Java's autoboxing and unboxing — the automatic conversion between primitives (like int) and their wrapper objects (like Integer). The article covers why both type systems exist, how the compiler silently inserts conversions when you use primitives with collections, and walks through a worked example (a quiz-score tracker) to show boxing and unboxing happening in practice. It then digs into the real-world gotchas: NullPointerException from unboxing a null wrapper, the Integer cache breaking == comparisons, performance costs from boxing in tight loops, and overload resolution quirks — wrapping up with concrete best practices for when to use primitives vs. wrapper types.

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