Java 27

The default garbage collector is now G1, potentially improving application performance and reducing memory overhead without configuration.

Oracle has announced the General Availability of Java 27 (JDK 27), making build 35 the official release ready for production. This release includes nine JDK Enhancement Proposals (JEPs), introducing significant updates such as making G1 the default garbage collector, enhancing TLS with Post-Quantum Hybrid Key Exchange, and offering previews for features like Lazy Constants and Structured Concurrency. Additionally, the release defaults to Compact Object Headers, includes JFR In-Process Data Redaction, and features the Vector API in its twelfth incubator phase. As is customary, Java 27 also incorporates numerous smaller improvements and bug fixes, with contributions from a wide range of developers and testers.

The inclusion of nine JEPs in Java 27 signals a continued push towards performance and security enhancements within the Java platform. The adoption of G1 as the default garbage collector aims to provide more predictable pause times and better throughput, impacting applications that were previously reliant on older collectors. Furthermore, advancements in TLS with post-quantum cryptography readiness address future security concerns, while previews of features like Structured Concurrency and Lazy Constants indicate ongoing efforts to modernize Java's concurrency and initialization models.

Developers can anticipate a more efficient and secure runtime environment with Java 27, as features like Compact Object Headers and JFR data redaction aim to reduce memory footprints and enhance data privacy by default. The continued iteration on the Vector API suggests its increasing maturity and potential for high-performance computing workloads. These changes collectively position Java 27 as a release focused on foundational performance improvements and forward-looking security and concurrency paradigms, readying the platform for evolving computational demands and threats.