fix jlink task

[siordache]

See beryx/badass-jlink-plugin#61

[tobiasdiez]

Thank you, very much appreciated! Is there a general approach to debug these kind of problems and to discover which modules to add to forceMerge (i.e. is there a similar statement as suggestMergedModuleInfo for mergedModule)?

[siordache]

forceMerge is usually needed when some non-modular artifacts in your dependency graph use code that was previously part of the JDK but it was removed in the newer releases. The pom.xml associated with such a non-modular artifact does not mention that the artifact depends on the removed code (because the artifact was published when this code was still available in the JDK). That's why the plugin cannot detect all dependencies between artifacts in such situations.

This table shows the modules removed in JDK-11 and their replacements. When you find out that one of your non-modular dependencies requires code from one of these removed modules, you usually need to add the corresponding replacement library to your dependencies block and pass the prefix of the associated JAR file to forceMerge. Force-merging a library can create a cascading effect, so you may need to force-merge some additional artifacts.

I don't have a rigorous approach to find out which artifacts should be force-merged. Most of the time I just execute the jlink task and look for the module not found: ... error messages. Then I update the forceMerge calls and repeat the process. A couple of iterations are usually enough.