Calling a Groovy function from Java

Question

How do you call a function defined in a Groovy script file from Java?

Example groovy script:

def hello_world() {
   println \"Hello, world!\"
}
         


        

Answer 1

The simplest way is to compile the script into a java class file and just call it directly. Example:

// Script.groovy
def hello_world() {
    println "Hello, World!"
}

// Main.java
public class Main {
    public static void main(String[] args) {
        Script script = new Script();
        script.hello_world();
    }
}

$ groovyc Script.groovy
$ javac -classpath .:$GROOVY_HOME/embeddable/groovy-all-1.7.5.jar Main.java
$ java -classpath .:$GROOVY_HOME/embeddable/groovy-all-1.7.5.jar Main
Hello, World!