从Groovy导入Scala

Question

Is there a way, preferred standard way to import Scala code (local jar, or local maven, or remote artifactory)?

We are using Groovy on Grails, and some library we want to use are written in Java or Scala. Considering they are all JVM languages, there must be a way to interplay.

I've search the net, but have not get a clear answer.

Answer 1

Both Scala and Java compiles into Java Bytecode ( .class files) and packed as .jar files. It's same bytecode, and can be used from any other JVM language under same classpath.

So your app can mix java bytecode produces from any other JVM language, including Java, Groovy, Scala, Clojure, Kotlin, etc. You can put such jars into /lib dir (if your Grails version supports this; it's less preferred way) or as dependency from Maven repository (local or remote). Then you can use such classes from your code

See:

• https://en.wikipedia.org/wiki/Java_bytecode
• http://grails.github.io/grails-doc/2.4.x/guide/conf.html#dependencyResolution for grails 2.4.x
• http://grails.github.io/grails-doc/latest/guide/conf.html#dependencyResolution for latest grails

PS there could be some incompatibilities with some classes, because of different nature of sources languages. But in general it should work.

Answer 2

Did some simple tests. In hello-world example, just use

groovy -cp the-assembly-SNAPSHOT.jar main-file.groovy

And in the main-file.groovy , should have an import , like in Java/Scala