Most of the API changes are in support of adding modules to the platform, both as a language structure in
javax.lang.model.* as well as another interaction point in
javax.annotation.processing in the
Filer and elsewhere. A small API change was also done to better support repeating annotations. A more detailed summary of the API changes is included in the MR material.
The API changes are intended to be largely compatible with the sources of existing processors, their binary linkage, as well as their runtime behavior. However, it would be helpful to verify that your existing processors work as expected when run under JDK 9. JDK 9 early access binaries are available for download. Please report experiences running processors under JDK 9 as comments here or to me as email. Feedback on the API changes can be sent to