Flex - Gerar Relatorio JasperViewer no lado do cliente

package auditoria;

import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jasperreports.engine.JRAbstractExporter;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JREmptyDataSource;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRExporterParameter;
import net.sf.jasperreports.engine.JRPrintPage;
import net.sf.jasperreports.engine.JRRuntimeException;
import net.sf.jasperreports.engine.JasperExportManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.export.JExcelApiExporter;
import net.sf.jasperreports.engine.export.JRPdfExporter;
import net.sf.jasperreports.engine.export.JRRtfExporter;
import net.sf.jasperreports.engine.util.JRLoader;
import net.sf.jasperreports.view.JasperViewer;
import flex.messaging.FlexContext;
import flex.messaging.FlexSession;

@SuppressWarnings("unchecked")
public class GenerateRTF{

	private String uuid;
	private String sessionid;
	private List<JasperPrint> jasperPrintList;

	public Object generate(Map<String, Object> params) {

		FlexSession session = FlexContext.getFlexSession();
		
		uuid = params.get("uuid").toString();
		
		sessionid = params.get("sessionid").toString();
//
		try {
			jasperPrintList = (List<JasperPrint>) session.getAttribute(sessionid);
		} catch (Exception e) {
		}
//		
		if (jasperPrintList==null) {
			jasperPrintList = new ArrayList<JasperPrint>();
		}
		
		Map map = new HashMap();
		
		map.putAll(params);

		MapUtil.castToJRBean(map);

		jasperPrintList.add(gerarJasperPrint(map));

		session.setAttribute(sessionid, jasperPrintList);  // sessionid guarda a lista 

		byte[] rtf = gerarRTFArray();

		Boolean	isRemote = ((String)map.get("isRemote")).equalsIgnoreCase("true");
		
		if(isRemote){

			String contextRoot = FlexContext.getHttpRequest().getRequestURL().toString();
			
			contextRoot = contextRoot.substring(0,contextRoot.indexOf("messagebroker/amf"));

			session.setAttribute(uuid, rtf);  	// uuid guarda a imagem do report
								
			String url = contextRoot + "dynamic-pdf?id=" + uuid +"&jsessionid="+ sessionid;
					
			return url; 
			
		}else{
			
			return rtf;
		}
	}

	private JasperPrint gerarJasperPrint(Map map) {

		String jasperFile = (String)map.get("reportName");
		String pathJasper = ((String)map.get("pathJasper")) + jasperFile + ".jasper";
		JasperPrint jasperPrint = null;
		
		try {

			JasperReport jasperReport = (JasperReport) JRLoader.loadObject(pathJasper);
						
			if (map.containsKey("REPORT_DATA_SOURCE")) {
				JRDataSource ds = (JRDataSource) map.get("REPORT_DATA_SOURCE");
				jasperPrint = JasperFillManager.fillReport(jasperReport, map, ds);
				
				JExcelApiExporter xlsExporter = new JExcelApiExporter();
				xlsExporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint);
				xlsExporter.setParameter(JRExporterParameter.OUTPUT_FILE_NAME,jasperFile+".xls");
				System.out.println("Exporting report...");
				xlsExporter.exportReport();
				System.out.println("Done!");
				
				
				
				
			} else {
				jasperPrint = JasperFillManager.fillReport(jasperReport, map, new JREmptyDataSource());
			}
			
		
		}catch (JRException e) {
			
			e.printStackTrace();
			
		}catch (JRRuntimeException e) {
			
			System.out.println("ERRO NO JRXML");
			
			e.printStackTrace();
		}catch (Exception e) {
			
			e.printStackTrace();
		}
		
		return jasperPrint;
	}
	
	
	private byte[] gerarRTFArray(){

		JasperPrint jasperPrint = appendReports();

		byte[] pdf = null;
		
		try {
			
			pdf = JasperExportManager.exportReportToPdf(jasperPrint);
			
		} catch (JRException e) {

			e.printStackTrace();
			
		}
		
		return pdf;
	}
	
	private JasperPrint appendReports(){
		
		JasperPrint jasperPrint = null;
		JasperPrint pages = jasperPrintList.get(0);

		synchronized (pages)
		{
			if (jasperPrintList.size()>1) {

				jasperPrint = jasperPrintList.get(jasperPrintList.size()-1);
				
				List<JRPrintPage> list = jasperPrint.getPages();

				for (JRPrintPage jRPrintPage : list) {
					pages.addPage(jRPrintPage);
				}
			}
		}
		
		return pages;
	}
	
}

package auditoria;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
 
public class PDFResourceServlet extends HttpServlet { 
    private static final long serialVersionUID = 8178787853519803189L; 
 
    protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException{ 
        
    	doPost(req, res); 
    } 
 
    protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
    	
        String id = (String)req.getParameter("id"); 
       
        if (id != null) {
        	
            HttpSession session = req.getSession(true); 
            
            try {
            	
                byte[] pdf = (byte[])session.getAttribute(id); 
 
                if (pdf != null){
                	
                	res.setHeader("Expires", "0");
                	res.setHeader("Cache-Control", "must-revalidate, post-check=0, pre-check=0");
                	res.setHeader("Pragma", "public");
                	res.setContentType("application/pdf"); 
                	
                    res.setContentLength(pdf.length); 
                    res.getOutputStream().write(pdf); 
                    session.invalidate();                 
                }else{
                	
                    res.setStatus(404); 
                } 
            }catch (Throwable t){
            	
                System.err.println(t.getMessage()); 
            } 
        } 
    } 
}