WTF, Java 9?! :scream:

Some things break on Java 9. Here I collect short, self contained, correct (or not) examples demonstrating what fails and (hopefully) how to fix it. Note that there is no judgment involved! This is not about whether the things should break or not and whether that's good or bad - it's just about what does break.

You could be looking at this either as a beautiful static site or as a GitHub repository.


So far we have "trouble" with...


The demos are organized as Maven modules (I use Maven 3.5.0). You can run them individually (in their respective folders) or consecutively (in the root folder) with mvn clean test, maybe throwing in -fae (fail at end) to execute all even if some fail.

On Java 8, the build should be successful. To run it on Java 9:

If you're on Linux, you can use the switch-to-java script. Called with either 8 or 9 as parameter, it makes sure that the build runs on the appropriate version.


Contributions are very welcome! To make sure they have high quality, make sure your demo checks as many of these boxes as possible:

If you have any questions, open an issue. If want to contribute either open an issue or a PR, depending on how much you already have.

Once again, contributions are welcome! :)