Java 21 LTS Features Overview and Practical Guide
This article walks readers through upgrading from Java 11 to the Java 21 LTS by explaining the six‑month release cadence, JEP process, and SDKman setup, then demonstrates practical code examples for twelve new features—including preview Unnamed Classes, String Templates, Scoped Values, Structured Concurrency, Vector API, Virtual Threads, and Generational ZGC—highlighting their motivations, benefits, and production considerations.