Loading groovy classes with conflicting names

Question

I use GroovyScriptEngine inside my Java application to load code dynamically from different sources. Let's say I have two folders sources_A\ and sources_B\.

GroovyScriptEngine engine = new GroovyScriptEngine(new String[]{
    "sources_A", "sources_B"
});

Within each folder I have Groovy packages and classes that I wish to instantiate arbitrarily at runtime.

Problem: Some of these classes have the same (full) name in both folders.

So there is an ambiguity when I run:

engine.loadScriptByName("some.package.SomeClass").newInstance()

Of course, I could create two different engines:

GroovyScriptEngine engine_A = new GroovyScriptEngine(new String[]{"sources_A"});
GroovyScriptEngine engine_B = new GroovyScriptEngine(new String[]{"sources_B"});

But then I run into issues when two objects instantiated from these two different engines have to interact with each other:

object_from_A.someMethod(object_from_B);

Error: argument type mismatch at line ** in method foo in file bar.groovy

(Needless to say that there is no type mismatch: the object has the right type but is not recognized due to the different engine)

In short, do you have a solution to either:

• The one-engine solution with some way to disambiguate which source folder is used?
• The two-engine solution with some way to have objects from the two different engines to work together?

Answer 1

Java (and Groovy) classloader identifies a class by its fully qualified name and can load it only once. So, no, you can't load 2 classes of the same name (only one will be loaded).