Appendix: Compatibility with earlier versions and migration

JENV V11.0A is an implementation of the “Java Platform, Standard Edition” (Java SE^TM) for BS2000.

With OpenJDK 9, a module concept was introduced in Java. Due to this module concept, neither source nor binary compatibility with versions < V9.0A can be guaranteed. 

In addition, a distinction must be made between incompatibilities in the OpenJDK implementation and those in the BS2000 portation.