How to set parameter "unlabelled data" of Rapidminer's "Apply Model" in Java?

Question

I am using .rpm file to use a Rapidminer process in java. I have also retrieved the model in my java code. Now the problem is I want to simulate a data example in java via ApplyModel operator. How do i do that?

RapidMiner.setExecutionMode(RapidMiner.ExecutionMode.COMMAND_LINE);
RapidMiner.init();
Process pr = new Process(new File("C:\\Users\\Ameer Abdullah\\.RapidMiner\\repositories\\Local Repository\\naivebayesmodel.rmp"));
Operator op = pr.getOperator("Apply Model");
op.setParameter( );             //here I want to change parameter for unlabelled data input port          
pr.run();