Incorrect argument type encountered in function or method invocation. in main ~ foundjava

I am working with ORACLE SOA & OSB version 11.1.1.5.0. This error occurs if you use Oracle Business Rules and you forget to pass all the objects defined in your decision function. To elaborate: if in your decision function you have defined as inputs, let’s say, the objects Customerand Address, but in your code you only pass as input the object Customer, then you will get the error message above. To fix it either pass both objects, or remove the unused object from the input settings of your decision function.

The actual error oracle outputs is rather misleading. I spent three hours trying to find out what’s going on.