How to "include" common methods in groovys - groovy

Question

I have developed a number of groovys used as plugins by Serviio.
Many of the methods used by these plugins are common, but when changes are made, each plugin needs to be updated. Therefore I want to "include" those methods in each plugin from a tools.groovy. I have tried 2 different approaches suggested in other posts.
I tried using
evaluate(new File("C:\\Program Files\\Serviio\\plugins\\tools.groovy"))
at the start of each plugin where tools.groovy just has
class Tools{method1{return}method2{return}}
but when executing the plugin I get
Caught: groovy.lang.MissingMethodException: No signature of method: Tools.main() is applicable for argument types: () values: []
If I then add
void main(args) { }
to class Tools, the error goes away but that Tools.main is run instead of the plugin.main and I get no output.
My second approach as suggested was to use
def script = new GroovyScriptEngine( '.' ).with {
loadScriptByName( 'C:\\Program Files\\Serviio\\plugins\\tools.groovy' )
}
this.metaClass.mixin script
This however gives the error
unexpected token: this # line 55, column 2.
this.metaClass.mixin script
Any suggestions on how to make either of these solutions work would be appreciated.

Answer 1

Did you try defining a common base script and giving it as a compiler configuration.
http://groovy.codehaus.org/Embedding+Groovy
From the groovy documentation...
class ScriptBaseTest {
#Test
void extend_groovy_script() {
def compiler = new CompilerConfiguration()
compiler.setScriptBaseClass("ScriptBaseTestScript")
def shell = new GroovyShell(this.class.classLoader, new Binding(), compiler)
assertEquals shell.evaluate("foo()"), "this is foo"
}
}
abstract class ScriptBaseTestScript extends Script {
def foo() {
"this is foo"
}
}