Search code examples
javagroovyembedding

Variable of same class in separate contexts

I'm trying to embed groovy in java application and got a weird problem. Let's say I have this class defined in groovy script:

class MyClass {
    String a;
}

Then I instantiate it and put it into my application context scope (Map<String, Object> stored in my main application and providing a common storage between scripts).

MyClass c = new MyClass()
c.a = "Hello world!"
appContext.share.put("myclass.instance",c)

Then, in other script (that is run separately, with it's own context, but from the same sources including MyClass.groovy file), I try to read the variable back:

MyClass c = (MyClass) appContext.share.get("myclass.instance")

And get a spectacular exception about not being able to cast MyClass instance to MyClass :) .

Basically I understand what could be the problem, each time I compile the script it creates new instances of classes with different ID's but same names, and they are incompatible with each other. Question is, how can I do what I am trying to do without serializing/deserializing all shared objects and without using reflection?

It has to be noted that I can't move the MyClass class to Java code, it has to remain in the script as it is part of script logic.

Thanks in advance.

Solution

  • What if you try casting with appContext.share.get("myclass.instance") as MyClass ? as performs a more "harsh" cast, it can even cast Map to a class. It is like c.properties = appContext.share.get("myclass.instance").properties.