On 16.01.2017, at 14:50, Marshall Schor <m...@schor.com> wrote: > > I'm fine with either approach. I suspect different projects may find each > approach, or even a 3rd approach (e.g., Peter's idea of just migrating at some > point), best for their project. I would hope to include a short chapter in > the > uv3-guide describing a bit of a cookbook for each of these approaches :-). > > One thing I don't yet understand: if we have two "generated-sources" in > target/, > each defining identically named JCas classes, the compile targets for these > can't both be target/classes/. Anyone know the Maven convention for handling > this so two different JARs can be built?
I expect that we'd need something like: 1) 1 execution for the maven-jcasgen-v2-plugin 2) 1 execution for the maven-jcasgen-v3-plugin 3) 1 execution of the maven-compiler-plugin compile the v2 code 4) 1 execution of the maven-compiler-plugin compile the v3 code 5) 1 execution of the maven-compiler-plugin compile the main code against either the v2 or the v3 code - doesn't matter too much because the API is the same and they should be binary compatible 6) 1 execution of the maven-jar-plugin to package the main classes and attach them to the artifact 7) 1 execution of the maven-jar-plugin to package the v2 jcas classes and attach them to the artifact 8) 1 execution of the maven-jar-plugin to package the v3 jcas classes and attach them to the artifact However, I cannot figure out atm if/how it is possible to tweak Maven such that we can control the sourcepaths properly in steps 3, 4, and 5. The "includes/excludes" of the compiler plugin are no help here because they are relative to the source paths and the v2 and v3 classes will have the same names/packages. The maven-build-helper plugin is also no help, because it only allows to *add* source folders, but not to remove them... I general, I've found one approach that works with excludes in the Maven JAR plugin, but that only kicks in after everything has been compiled - we probably are going to hit problems when we start even compiling. http://blog.sonatype.com/2010/01/how-to-create-two-jars-from-one-project-and-why-you-shouldnt/ That article also mentions the user of the Maven Assembly Plugin for complicated cases. I didn't dig into detail into how DL4J does it for their native API and platform-specific library JARs where they use classifiers. I just found another approach which shows how to use multiple POMs but only a single source folder - but that just for completeness. I don't see how it would help: https://maven.apache.org/guides/mini/guide-using-one-source-directory.html Cheers, -- Richard
