Hi, Apache Tomcat needs to add the following options when running on Java 9:
--add-modules=java.se.ee --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.rmi/sun.rmi.transport=ALL-UNNAMED The first is because it depends on javax.xml.ws.WebServiceRef and javax.xml.ws.WebServiceRefs. We could work around this by shipping our own implementations but that sort of duplication should not be necessary. The second and third are required by Tomcat's memory leak detection and prevention code. In an ideal world, web applications wouldn't have memory leaks. Unfortunately, the world isn't ideal and the memory leak detection and prevention code has proven immensely valuable over the years. The problem we have is that Tomcat needs to run on Java 9 though 6. If the above options aren't provided, Java 6 through 8 are fine but on Java 9 at best the users see a bunch of errors and at worst Tomcat won't start. If the above options are included, Java 9 is fine but then Tomcat fails to start on Java 6 though 8. What is the recommended approach for applications that need to use one or more of the options above and need to start cleanly on multiple Java versions including 9 and earlier using a single, common start-up script? To date, Tomcat has always been Java version agnostic as long as at least the minimum Java version as specified by the Java EE spec has been used. We really don't want to have to change that. Suggestions welcome. Mark
