Default JDK Updates

Change effective on 18 January 2018

Heroku’s support for Java, Scala, Clojure, Groovy and JRuby now uses OpenJDK 8u161 as the default JDK version and OpenJDK 9.0.4 as the default JDK 9 version. The default for Java 1.7 remains OpenJDK 7u151. Please visit the Dev Center for more information on Java version support.