Getting values from a query that retrieves two entites in jasper reports

Question

i am using ireport 4.1.1 with hibernate jpa and I have a query that retrieves two entities:

select a,b from TableA a left join a.tableBList b

I am trying to get the value of a and b, in java, it returns an array of objects (Object[]) with two items, but when I try to do this on jasper reports it gives me this error:

Exception in thread "main" net.sf.jasperreports.engine.JRRuntimeException: net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : fieldName

I think that i only need to replace fieldName with the name of the object that will be returned but I don'w know it and I have tried to find it but I have had no success, anyone of you can help me please???

Thanks in advance :)

Answer 1

This error is because your data is not mapping with beans property, or you can that your data pattern is not according to the beans property. I was having the same problem in my java project. And I sorted out that your data should be in a proper 2D array form, then I took sample data from somewhere and did this

String[][] data =
{{ "N263Y", "T-11", " 39 ROSCOE TRNR RACER"},
{ "N4087X", "BA100-163", "BRADLEY AEROBAT"},
{ "N43JE", "HAYABUSA 1", "NAKAJIMA KI-43 IIIA"},
{ "N912S", "9973CC", "PA18-150"}};

        JTable m = new JTable(data,headers);
try {

            JasperReport jasperReport = JasperCompileManager.compileReport(fileName);

            if(jasperReport != null )
               System.out.println("so far so good ");

            // Fill the report using an empty data source

            JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, params, new JRTableModelDataSource(m.getModel()) );//create());//con.connection);
            try{
            JasperExportManager.exportReportToPdfFile(jasperPrint, outFileName);
            System.out.printf("File exported sucessfully");
            }catch(Exception e){
                e.printStackTrace();
            }
            JasperViewer.viewReport(jasperPrint);

        } catch (JRException e) {
            JOptionPane.showMessageDialog(null, e);
            e.printStackTrace();
            System.exit(1);
        }

Note:

Your field name should start with small letters, moreover field names should be small as of the columns names ur providing within that data.

Hope this will help you.