how to get parameters defined in jasper file?

Question

I need to get the parameters defined in a jasper file so I can generate inputs depending of the type of these parameters to fill the report.
I'm working with jasperreports-5.0.0

Answer 1

JasperReport jasperReport = (JasperReport)JRLoader.loadObject(new File("report.jasper"));
JRParameter[] params = jasperReport.getParameters();

for(JRParameter param : params) {
  if(!param.isSystemDefined() && param.isForPrompting()){
     param.getName();
     param.getDescription();
     param.getDefaultValueExpression();
     param.getNestedTypeName();
  }
}