Groovy - including plantuml in a script

Question

Hi chaps, I found the code below on this website, however, I don't know what is the parameter for call below, how to replace it to works on my script:

parameter: @startuml\nBob->Alice:hello\n@enduml

code:

s = new net.sourceforge.plantuml.SourceStringReader("@startuml\nBob->Alice:hello\n@enduml")
FileOutputStream file = new FileOutputStream("c:/testGroovy2.png")
s.generateImage(file);
file.close()

source:

http://plantuml.com/code-groovy

thanks,

Raul