An example to generate a java class from a pkl file

[dev92]

Hi,
I am not using gradle to generate java files, if I have a vanilla java project using maven how to generate java code from a pkl file

I see an example using java -cp -jar pkl-codegen-java-0.25.2.jar -o generated example.pkl
When i use this I get following error:
Exception in thread "main" java.lang.NoClassDefFoundError: kotlin/jvm/internal/Intrinsics
at org.pkl.codegen.java.Main.main(Main.kt)
Caused by: java.lang.ClassNotFoundException: kotlin.jvm.internal.Intrinsics
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:527)
... 1 more

What should be the classpath for the jar?

[StefMa]

I don't know from where you have the jar file, but in general you have to add each and every jar file to the classpath that is a dependency of the java-codegen gradle module.
Another option would be to create a fatJar, this jar would include every dependency and your call would succeed.

In your specific crash, the Kotlin jar is missing 🙃

[dev92]

Thank you Stefan, so I have my own repo of an example app to test and in my pom.xml I mentioned a dependency to pkl-codegen-java
Maven downloaded it and I used the pkl-codegen-java.jar from m2 repository to try and generate java code from a pkl.

I think I am doing this the wrong way, what would be the best way to test pkl-codegen-java without using gradle?

[bioball]

You can use the pkl-tools fat jar, which includes all the dependencies needed for codgen.

Example:

printf "module Example\n\nfoo: String\n" > Example.pkl
curl -o pkl-tools-0.25.2.jar https://repo1.maven.org/maven2/org/pkl-lang/pkl-tools/0.25.2/pkl-tools-0.25.2.jar
java -cp pkl-tools-0.25.2.jar org.pkl.codegen.java.Main -o generated Example.pkl

[dev92]

Thank You Daniel that worked :)

[linux-china]

If you use JBang , and you can use following command for codegen.

$ jbang run --main org.pkl.codegen.java.Main "org.pkl-lang:pkl-tools:0.25.2" --help

or following command for cli

$ jbang run --main org.pkl.codegen.java.Main "org.pkl-lang:pkl-tools:0.25.2" --help

[otaviocv]

Is there a way to use that from a plugin within maven?

I was following another post from @linux-china but I couldn't make it work. I always get An exception occurred while executing the Java class. The specified mainClass doesn't contain a main method with appropriate signature. error.