JetBrains Runtime is a runtime environment for running IntelliJ Platform based products on Windows, Mac OS X, and Linux. JetBrains Runtime is based on OpenJDK project with some modifications. These modifications include: Subpixel Anti-Aliasing, enhanced font rendering on Linux, HiDPI support, ligatures, some fixes for native crashes not presented in official builds, and other small enhancements.
JetBrains Runtime is not a certified build of OpenJDK. Please, use at your own risk.
This page has instructions how to change the java runtime for IntelliJ IDEA Platform based IDEs. Current java runtime version can be verified in IDE's About screen.