JDK license issue for the runtime Java

[houshengbo]

Openwhisk is under apache license 2.0. We should be cautious about using JDK in runtime java repo or any other repo.
Oracle java is licensed under oracle BCL.
OpenJDK is licensed under GNU GPL.
Neither of them is friendly to Apache license.

Apache defines the relationship with other licenses here: https://www.apache.org/legal/resolved.html

OpenJDK license can be found here: http://openjdk.java.net/legal/gplv2+ce.html
Oracle JDK license can be found here: http://www.oracle.com/technetwork/java/javase/terms/license/index.html

[houshengbo]

Based on my observation, the momentum of openwhisk runtime java, changing from oracle JDK to Docker Images for Eclipse OpenJ9 Version 8, https://hub.docker.com/r/adoptopenjdk/openjdk8-openj9/, can be accepted by Apache. However, I am no lawyer, and we still need confirmation about it.

The docker image we use contain OpenJDK binaries that are built with Eclipse OpenJ9. The full license can be found here: https://github.com/eclipse/openj9/blob/master/LICENSE, which is dual licensed under Eclipse Public License 2.0 and Apache License, Version 2.0.

We have to do all the other openwhisk repos to see if there are still oracle jdk or open JDk left, and replace them with "docker image for Eclipse OpenJ9".

[houshengbo]

Tracking this issue to be resolved:
OpenWhisk: apache/openwhisk#3607

[houshengbo]

Further discussion is going on here: apache/openwhisk#3607

[mrutkows]

regardless, we will need to remove the Oracle JDK as it is Category X (if we intend to release binaries) and understand it gets more restrictive with JDK 9.

[houshengbo]

Revisit this issue for further binary releases.