Hi Per,
I have had (very) good luck with a slightly different approach. Rather than 'groovy -jar myapp.jar' I went with 'java -jar myapp.jar'. And this had another, somewhat unexpected, benefit. Building my app with shadowJar <https://gradleup.com/shadow/> (thanks to the help I received here) it bundled all of groovy, all my library dependencies (database drivers, etc), and my app into my jar file. As a result, I don't even need to install groovy on a target machine - just copy the one jar file (myapp.jar) to the target machine and run it via 'java -jar myapp.jar' and everything completely works. Of course this assumes that Java has been installed but that's pretty ubiquitous these days and a requirement anyway. And I don't have to worry about the version of groovy that happens to be installed on that machine as the execution will use the version of groovy that is inside my jar file. You can review a working example of this at https://github.com/mre-code/groovysql. Now unfortunately, due to Java <https://dev.java/learn/modules/strong-encapsulation/> 's newer encapsulation direction (which does make a lot of sense) I ended up needing to provide a shell wrapper to provide all of the -add-opens settings required for (older) Java database drivers (which I use for this app). Now if it weren't for those older Java database drivers which are using reflection I would not need the little shell wrapper and could just use 'java -jar groovysql.jar' (or even the binfmt approach discussed in the groovysql repository where you can just make the jar file executable and run it as 'groovysql' after removing the .jar extension from the file). For background, the little shell wrapper is located in src/main/bin/groovysql in that repository. So in order to run my app, all that anyone needs to do is to copy my jar file and the little shell wrapper from the Releases and place them somewhere in their PATH and it's ready to run. No groovy install, no database driver installs, no configuration, just go. Hope this helps, Steve From: Per Nyfelt <p...@alipsa.se> Sent: Saturday, February 22, 2025 2:34 PM To: users@groovy.apache.org Subject: Groovy -jar Hi, I find myself missing a way to execute groovy jars e.g: `groovy -jar someapp.jar`. As a workaround i can do something like the following in bash (error handling etc. omitted) #!/usr/bin/env bash # takes a single parameter (the path to the jar file to execute - it assumes the Main-Class attribute has been set) jarName="$1" mainClass=$(unzip -p "$jarName" "META-INF/MANIFEST.MF" | grep 'Main-Class:' | awk '{ print $2 }' | tr -d '\r') java -cp $jarName:$GROOVY_HOME/lib/* $mainClass But it would be nice to support this "natively" in groovy with `groovy -jar` Has support for this been discussed before? Best regards, Per
