JasperReports: getting java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Number

Question

I am trying to generate excel reports from Java . I am using Spring on Java side and iReport to develop the jasper files. I am getting ClassCast exception although the report runs fine on iReport . The language I am using at iReport side for report is Java .

The whole error Console is:

java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Number
    at net.sf.jasperreports.engine.JRAbstractExporter.getNumberCellValue(JRAbstractExporter.java:1198)
    at net.sf.jasperreports.engine.JRAbstractExporter.getTextValue(JRAbstractExporter.java:1139)
    at net.sf.jasperreports.engine.export.JRXlsExporter.createTextCell(JRXlsExporter.java:737)
    at net.sf.jasperreports.engine.export.JRXlsExporter.exportText(JRXlsExporter.java:684)
    at net.sf.jasperreports.engine.export.JRXlsAbstractExporter.exportPage(JRXlsAbstractExporter.java:1195)
    at net.sf.jasperreports.engine.export.JRXlsAbstractExporter.exportReportToStream(JRXlsAbstractExporter.java:940)
    at net.sf.jasperreports.engine.export.JRXlsAbstractExporter.exportReport(JRXlsAbstractExporter.java:629)
    at com.ultimatix.dao.SubmissionReportJasperDaoImpl.mainReportXLS(SubmissionReportJasperDaoImpl.java:590)
    at com.ultimatix.service.SubmissionReportJasperServiceImpl.excelDownload(SubmissionReportJasperServiceImpl.java:159)

Is there some mismatch of data types within the report or some other issue. Since iReport generates the o/p, I have no clue what is wrong at Java end.

My Implementation:

    String mainDir="D:/Reports _ B_Type/";

        String[] sheetNames={"Contract Details","Quick Selection","Basic Details","Billing Related Parameter","Discounts Applicable","Charges Applicable","Other Parameter","Slab-Wise Rates"};

        Map<String, Object> parameters = new HashMap<String, Object>();
        contractId = (String) contractData.get(DBConstants.PROC_PI_CONTRACT_ID);
        versionNo = (String) contractData.get(DBConstants.VERSION_NO);
        String sql=SQLQuery.getCommonHeaderDetailForFCmVersion();
        ByteArrayOutputStream os1 = new ByteArrayOutputStream();
        try
        {
            jdbcTemplate = new JdbcTemplate(dataSource);
            contractDataList = jdbcTemplate.queryForList(sql,new Object[] {contractId,versionNo});
            for (Map<String,Object> row : contractDataList) {
                contractingCompany=(String) row.get(DBConstants.FCM_CONTRACT_INFO_CONTRACTING_COMPANY);
                customerName=(String) row.get(DBConstants.FCM_CONTRACT_INFO_MV_CUSTOMER_NAME);
                startDate=(String) row.get(DBConstants.FCM_CONTRACT_INFO_MV_CONTRACT_START_DATE);
                endDate=(String) row.get(DBConstants.FCM_CONTRACT_INFO_MV_CONTRACT_END_DATE);
                if(null != row.get(DBConstants.FCM_CONTRACT_INFO_MV_TOTAL_CONTRACT_VALUE))
                {   
                    tcsContractValue= row.get(DBConstants.FCM_CONTRACT_INFO_MV_TOTAL_CONTRACT_VALUE).toString();
                }
                contractStatus="E";
            }

            /*parameters to be passed in report */

            parameters.put("ContractId", contractId); 
            parameters.put("VersionNo", versionNo);
            parameters.put("SUBREPORT_DIR",mainDir);
            parameters.put("ContractingCompany",contractingCompany);
            parameters.put("CustomerName",customerName);
            parameters.put("StartDate",startDate);
            parameters.put("EndDate",endDate);
            parameters.put("TcsContractValue",tcsContractValue);
            parameters.put("ContractStatus",contractStatus);

            connection = DataSourceUtils.getConnection(dataSource);

            String reportTemplatePath = null;//path to find the template report


            String fileSep = File.pathSeparator;

            if(fileSep.equals(":") ){

            }else{
                reportTemplatePath =mainDir + "Main Report.jasper";
            }
            JasperPrint jasperPrint;

                jasperPrint = JasperFillManager.fillReport(
                        reportTemplatePath,parameters,connection);

            JRXlsExporter exporterXLS = new JRXlsExporter();

            exporterXLS.setParameter(JRXlsExporterParameter.JASPER_PRINT, jasperPrint);

            exporterXLS.setParameter(
                    JRXlsExporterParameter.IS_REMOVE_EMPTY_SPACE_BETWEEN_ROWS,Boolean.FALSE);

            exporterXLS.setParameter(JRXlsExporterParameter.IS_ONE_PAGE_PER_SHEET,
                    Boolean.TRUE);
            exporterXLS.setParameter(JRXlsExporterParameter.SHEET_NAMES,sheetNames);
            exporterXLS.setParameter(
                    JRXlsExporterParameter.IS_DETECT_CELL_TYPE, Boolean.TRUE);
            exporterXLS.setParameter(
                    JRXlsExporterParameter.IS_WHITE_PAGE_BACKGROUND, Boolean.TRUE);
            exporterXLS.setParameter(
                    JRXlsExporterParameter.CREATE_CUSTOM_PALETTE,Boolean.TRUE);//to generate closest matching color when report generated from java end.

try{
            exporterXLS.setParameter(JRExporterParameter.OUTPUT_STREAM, os1);
            **exporterXLS.exportReport();**
}
catch(Exception e)
{
    e.getMessage();
    e.printStackTrace();
}`enter code here`

This is where i get the exception.

Answer 1

Sounds like a bug that's been fixed at JasperReports trunk revision 6340.

Build a JasperReports jar from the SVN trunk (or patch the 5.0.1 sources) to check if it's the same problem.