Accessing variable's instance through debug information

Hello

I'm trying to create plugin wich will allow to copy JSON representation of variable's or expression's instance from debug tool windows (variables, watches, inspection, etc.)
Using BaseValueAction from community edition sources I created own action, but I'm stuck with obtaining actual instance from com.sun.jdi.Value through DebugProcess

For example, I can call some method from ObjectReference by it's Method instance using following code:

result = debugProcess.invokeInstanceMethod(evaluationContext, objRef, method, Collections.emptyList(), 0);     

But how can I get instance of "this" for specified ObjectReference?
I just need to get whole expression value instance, not it's descriptor, to pass it to Gson

Can anyone help with this question?