Upgrading Java Applications from JDK 1.8 to JDK 21 with Spring Boot 3
This guide documents key technical adjustments required when modernizing a legacy Java application—from JDK 1.8 and Spring Boot 2.x to JDK 21 and Spring Boot 3.2+. The migration involves breaking API changes, dependency updates, and configuration refactoring across multiple layers: servlet stack, security, persistence, serialization, and toolin ...
Posted on Mon, 17 Aug 2026 16:51:34 +0000 by jamcoupe