setting report parameter's value from Java scriptlet

[asookaziangmail.com]

I am trying to set a non-input parameter's value from a  Java scriptlet which extends as JRDefaultScriptlet follows:

@Override    public void beforeReportInit() throws JRScriptletException {        Map<String,JRFillParameter> parametersMap = super.parametersMap;        JRFillParameter fillParam = parametersMap.get("myParam");        fillParam.setValue("myParamValue");        //reset map        super.parametersMap.put("myParam", fillParam);           }[/code]

The new value for the myParam parameter is either not beign set properly or not taking effect at the proper/expected timing.  The value of the param is evaluated/used in a DynamicQueryController similar to this demo: https://www.youtube.com/watch?v=tvddKCeWPBY.

Please identify how to resolve this problem.  Generally speaking, how would one set a non-input parameter value programmatically?  thanks.

Jasper Reports 5.6.1.