Change effective on 17 April 2018
Heroku’s support for Java, Scala, Clojure, Gradle, and JRuby now includes the option of using JDK 8u171, 8u172, or 10.0.1. To set the JDK version for an application, create a
system.properties file in the root directory of your project and put the following code in it:
For a complete list of supported versions, see the Dev Center documentation for Java. For more information on OpenJDK 8u171 and 8u172, see the OpenJDK documentation for Java 8. For more information on JDK 10.0.1, see the OpenJDK documentation for Java 10.