Fedora 27 includes a technology preview of Java 9, offered through the
java-9-openjdk-devel and new
Java 8 remains the default JDK for this release. The inclusion of Java 9 / OpenJDK 9 will allow developers to develop and test their applications for the next version of Java in parallel while everyone can continue using the stable Java 8 for daily use.
More information about the new features of OpenJDK 9 is available from the OpenJDK website.
In earlier versions of Fedora, Java applications installed from RPMs were run in the JVM that was found using the
PATH environment variable. From this release, Java applications will be run using the default system JVM, which will be OpenJDK 8 in Fedora 27, without refering to
PATH. Users will still be able to override the default by using the
JAVA_HOME environment variable.
More detail about this revised configuration can be found on the change page.