ExecuteQueryForCollection override works in 10.1.2, not 10.1.3EA

Question

I've overridden executeQueryForCollection in a ViewObjectImpl and it was working in JDev 10.1.2. I'm experimenting with 10.1.3, so I copied my Application and imported it. I'm getting the following error:
oracle.jbo.JboException: JBO-29000: Unexpected exception caught: java.lang.ClassCastException, msg=[Ljava.lang.Object;
Here is a snippet of the code with the error:
protected void executeQueryForCollection(Object qc, Object[] params, int noUserParams)
// TODO: Override this oracle.jbo.server.ViewObjectImpl method
String submissionType = null;
if (params != null)
System.out.println("length.params()="+params.length+
", noUserParams="+noUserParams);
if (params.length > 0)
// This seems to be the line at which it blows up:
submissionType = (String) params[0];
System.out.println("submissionType="+submissionType);
The printlns are for debugging only. It looks like params[0] is no longer being passed as a String. It is being passed from a ViewLink. I suspect that I can fix this, if I can determine what class the parameter is, since I'll bet there is a method that will return a String. In 10.1.2, this is definitely a String containing either "A" or "D".

Answer 1

BINGO!
I wasn't sure, so I checked - sure enough, the bind variable style was set to "Oracle Named". So as an experiment, I changed it to "Oracle Positional", and upon testing, I see that the parameters now contain the String values that I am expecting. I still have a bug that is causing a Null value error, that I will have to find and fix, but I suspect that this is caused by some code I added to try to diagnose the original error.
So, thanks, Steve, for putting me on the right track. Question: If I were to retain "Oracle Named", what would be the right way to retrieve the parameter values?