public class ReportDataFactory {

    public static Collection generateCollection() {
        Vector collection = new Vector();
        collection.add(new Integer(1));
        collection.add(new Integer(2));
        return  collection;
    }
   
}

public class Record {
    private String field1;
    private String field2;
    public record() {
      super();
    }
    public record(String field1, String field2) {
      super();
      this.field1 = field1;
      this.field2 = field2;
    }
    public void setField1(String fld1) {
      this.field1 = fld1;
    }
    public String getField1() {
      return this.field1;
    }
    public void setField2(String fld2) {
      this.field2 = fld2;
    }
    public String getField2() {
      return this.field2;
    }
}

public class ReportDataFactory {

    public static Collection generateCollection() {
        Vector collection = new Vector();
        collection.add(new Record("xyz", "abc"));
        collection.add(new Record("yyy", "kkk"));
        return  collection;
    }
   
}

import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.export.*;


MyJavaBean bean;
String reportFileName = "C:/TEMP/case/forms/MYREPORT.jasper";
String jrxmlName = "C:/TEMP/case/forms/MYREPORT.jrxml";

//... populate the bean here before proceeding

//bean is ready, fill the report with the bean
JasperPrint jasperPrint9 = null;

JasperCompileManager.compileReportToFile(jrxmlName);

HashMap<String, Comparable> params = new HashMap<String, Comparable>();
//params.put("case_id",new Integer(0)); // need this only if your report accept parameters
                  
ArrayList<MyJavaBean> beanCollection = new ArrayList<MyJavaBean>();
beanCollection.add(bean);
JRBeanCollectionDataSource jrDataSource = new JRBeanCollectionDataSource(beanCollection);

jasperPrint9 = JasperFillManager.fillReport(reportFileName, params, jrDataSource);

// number of copies
int numCopies = 1; //hardcode to 1
for(int i = 0; i< numCopies; i++) {
        subjectPrintList.add( jasperPrint9 );
}

//choose exporter according to the format the user picked
String reportFormat = "PDF"; //hardcode to PDF
JRExporter exporter = new JRPdfExporter();
String contentType = "application/pdf";
String fileExtension = "pdf";
if ("DOC".equals(reportFormat)) {
        exporter = new JRRtfExporter();
        contentType = "applicaetion/msword";
        fileExtension = "doc";
}

exporter.setParameter(JRExporterParameter.JASPER_PRINT_LIST, subjectPrintList);
exporter.setParameter(JRExporterParameter.OUTPUT_STREAM, pdfOutput);
exporter.setParameter(JRExporterParameter.CHARACTER_ENCODING, "UTF-8");
exporter.setParameter(JRPrintServiceExporterParameter.DISPLAY_PRINT_DIALOG, new Boolean(true));
exporter.exportReport();

byte[] results = pdfOutput.toByteArray();

ServletOutputStream outstream = response.getOutputStream();
response.setContentType(contentType);
response.setContentLength(results.length);
response.setHeader("Content-disposition","inline; filename=\"Report." + fileExtension + "\"");
outstream.write(results);