Cannot compile when importing Processing library into eclipse

Question

I am trying to build a program using the Processing library in eclipse. The process should be relatively straightforward but I cannot compile even an empty processing program. I

Answer 1

I had the exact same problem after upgrading to JDK 9. I reported it as an issue here (https://github.com/processing/processing/issues/5371), and received confirmation that Processing 3 is incompatible with v9. For now, the only workaround is to downgrade to v8.