Chapter 1. Migrating OpenJDK 8 to OpenJDK 11 overview

The Migrating Red Hat build of OpenJDK 8 to Red Hat build of OpenJDK 11 guide describes changes in the Red Hat build of OpenJDK 11 release, including new features and deprecated or removed APIs, that might impact your migration from Red Hat build of OpenJDK 8. You can use the information in the guide to upgrade your Java applications in Red Hat build of OpenJDK 8 to Red Hat build of OpenJDK 11.

The OpenJDK project is known for its conservative approach to providing updates and for providing backward compatibility. However, to guarantee the evolution, security and stability of the project, the Red Hat build of OpenJDK project might sometimes introduce a few incompatibilities across major releases of Red Hat build of OpenJDK. These incompatibilities are relevant for the following scenarios:

  • When you use APIs that are considered obsolete or unsecure.
  • When you access internals of the project that are considered implementation details and not public or supported API details.

1.1. About the Red Hat build of OpenJDK 8u and 11u

OpenJDK is the free and open source reference implementation of the Java Platform, Standard Edition (Java SE). The Red Hat builds of OpenJDK are based on the upstream OpenJDK 8u, OpenJDK 11u, and OpenJDK 17u projects. The Shenandoah Garbage Collector is included in Red Hat build of OpenJDK versions 8, 11, and 17.

The Red Hat builds of OpenJDK provide the following benefits:

  • Multi-platform - The Red Hat build of OpenJDK is now supported on RHEL and Microsoft Windows, so you can standardize applications on a single Java platform across desktop, datacenter, and hybrid cloud environments.
  • Frequent releases - Red Hat delivers quarterly updates of JRE and JDK for the Red Hat build of OpenJDK 8, Red Hat build of OpenJDK 11, and Red Hat build of OpenJDK 17 distributions. These updates are available as archive, RPM, and Windows MSI-based installer files and container images.
  • Long-term support - Red Hat supports the recently released Red Hat build of OpenJDK 8, Red Hat build of OpenJDK 11, and Red Hat build of OpenJDK 17 distributions.

Additional resources