- Java 21 Record Patterns
1. Introduction Java records, introduced in Java 16, gave us a concise way to define immutable data carriers. But accessing the data inside a record still required calling accessor methods one at a time. Record Patterns, finalized in Java 21 (JEP 440), change that by letting you deconstruct a…
- Java 21 Other Improvements
1. Introduction Java 21 is a Long-Term Support (LTS) release, which means it is the version that most enterprises will upgrade to and run in production for years. While the headline features — virtual threads, pattern matching for switch, record patterns, and sequenced collections — get all the…
- Java 21 Migration Guide (17→21)
1. Introduction Java 21 is the next Long-Term Support (LTS) release after Java 17, released in September 2023. If your organization runs on Java 17 — which most modern Java shops do — Java 21 is the natural next upgrade target. It is not a “maybe someday” upgrade; it is a “plan this for your […]
- Java 21 Pattern Matching for switch
1. Introduction The switch statement has been part of Java since version 1.0, but for most of its life it was limited to matching exact values — integers, enums, and eventually strings. If you needed to branch based on the type of an object, you were stuck with if-else instanceof chains. That…
- Java 21 Unnamed Variables and Patterns
1. Introduction Every Java developer has seen this: you declare a variable because the language requires it, but you never actually use it. The IDE highlights it with a warning. Your linter flags it. Your team’s code review says “unused variable.” So you add a @SuppressWarnings(“unused”) annotation…