Updated
Updated · InfoWorld · Jul 29
JDK 27 Reaches RC With 9 Features, Making G1 Default Across All Environments
Updated
Updated · InfoWorld · Jul 29

JDK 27 Reaches RC With 9 Features, Making G1 Default Across All Environments

1 articles · Updated · InfoWorld · Jul 29

Summary

  • August 6 marks JDK 27’s initial release candidate, with the feature set frozen in rampdown phase 2 ahead of a final RC on August 20 and general availability on September 15.
  • Nine features headline the non-LTS release, led by G1 becoming the default garbage collector everywhere, structured concurrency, post-quantum hybrid TLS 1.3 key exchange, and primitive types in patterns, instanceof, and switch.
  • G1’s expansion beyond server environments aims to keep HotSpot on one default collector without materially hurting throughput, latency, memory footprint, or startup time.
  • JDK 27 also makes compact object headers the HotSpot default, cutting headers to 64 bits from 96 bits on 64-bit systems, while adding JFR in-process redaction, the Vector API, and PEM encoding support.
  • Oracle will support JDK 27 for six months as a short-term feature release, following JDK 26, which became generally available on March 17.

Insights

Will JDK 27’s new defaults—G1 everywhere and compact object headers—quietly boost most Java apps, or expose hidden performance tradeoffs?
Is Oracle’s hybrid post-quantum TLS in JDK 27 a practical security leap, or will bigger handshakes and compatibility risks slow adoption?
Why might JDK 27’s most important feature be invisible to developers: automatic JFR redaction that protects secrets by default?