Parameter Passing to Subreport Database Command in CR2008 using java

Question

Hi
In subreport i have  a query which accept parameter from the parameter list and works fine in crystal report designer but using java when i am trying to pass the parameter form it gives me error ERROR java.lang.nullpointer Exception. Below is the code attached to send parameter to subreport.
oReportClientDocument = new ReportClientDocument ();
            oReportClientDocument.open ( strRepPath, 0 );
            reportSource = oReportClientDocument.getReportSource ();
            oCrystalReportViewer = new CrystalReportViewer ();
            oCrystalReportViewer.setOwnPage ( true );
            oCrystalReportViewer.setOwnForm ( true );
            oCrystalReportViewer.setDisplayGroupTree ( false );
            oCrystalReportViewer.setDisplayToolbar ( true );
            oCrystalReportViewer.setPrintMode ( CrPrintMode.PDF );
          if ( fields != null )
                oFields = new Fields ();
                if ( !fields.isEmpty () )
                    o = null;
                    i = null;
                    o = new Object ();
                    i = fields.keySet ().iterator ();
                    while ( i.hasNext () )
                        o = i.next ();
                         setParamaterFields ( oFields, o.toString (), fields.get ( o ) );
                oCrystalReportViewer.setParameterFields ( oFields );

Answer 1

Hi David,
I guess you already have the parameters in the Main report.
Create a formula called Start_Date:
Min({?Date_Parameter})
Create another formula called End_date:
Max({?Date_Parameter})
Next, insert the sub-report with Order details table as the datasource.
Then, right-click the subreport and select Change Subreport Links > Move the Start_date formula and End_date to the 'Fields to link to' area and make sure you uncheck the option 'Select data in subreport based on field' for both of them.
Then, you also wish to link Salesman_Id, so move this field to the 'Fields to link to' area and from the drop-down for 'Select data in subreport based on field' select the Salesman_ID from the sub-report.
Now, right-click the sub-report and select Edit subreport. The design page of the Subreport opens up. Go to Report > Record Selection formula and it should show {?pmSalesman_ID} = . Edit the selection formula to include the start and end date like this:
*{?Pm-Salesman_ID} = and (ORDER_DATE >= {?Pm-@Start_date} or ORDER_DATE <= {?Pm-@End_date})*
Let me know how this goes!
-Abhilash