Can I use my existing version of Java Virtual Machine?

If you have Java 8 already installed then it might be ok to use with MettleCI.

MettleCI Workbench runs under the user mciworkb, so it uses the version of Java on that user’s path, as defined in their user profile. To validate your version of Java simply run java --version using mciworkb's Java command to know for certain.

MettleCI cannot use a JVM which is reported as an IBM JVM:

MettleCI can use an OpenJDK-based JVM:

If you make a mistake and attempt to run MettleCI components with an IBM JVM then MettleCI will produce the following error:

MettleCI Workbench: Java Vendor is IBM. Workbench requires non-IBM JVM of Version 1.8 or higher. Please see http://docs.mettleci.com for more information.

You’ll also get a similar error if you attempt to use a version of Java which is not v1.8 or greater.