iReport 编辑的报表，在jsp中导出到PDF的代码

此处使用了Java BeanCollection作为DataSource。

JSP页面代码：

<%@ page errorPage="error.jsp" %>
<%@ page import="reportDatasource.*" %>
<%@ page import="net.sf.jasperreports.engine.*" %>
<%@ page import="net.sf.jasperreports.engine.util.*" %>
<%@ page import="net.sf.jasperreports.engine.export.*" %>
<%@ page import="net.sf.jasperreports.j2ee.servlets.*" %>
<%@ page import="java.util.*" %><%@ page import="java.io.*" %>
<%@ page import="java.net.URLEncoder" %>
<%@ page import="javax.servlet.*" %>
<%@page language="java" contentType="application/x-msdownload"    pageEncoding="UTF-8"%>
<%
      String requestFileName = "LineReport";//报表的名称
      String reportFileName = requestFileName +".jasper";
      String fileDownName = "XXX报表";
      Map parameters = new HashMap();
     // parameters.put("ReportTitle", "Address Report"); //向报表传递参数   
      JasperPrint jasperPrint = JavaBeanListDataSoureFactory.createJasperPrintByJavaBeanList(reportFileName, parameters, LocationValueBeanFactory.getPageLoadTimeHistoryLineReportBeanCollection());        
    
       //输出
       PathClassPath classpath = new PathClassPath();
      String stringpath =  application.getRealPath("/reports/"+reportFileName);
     
      System.out.print("reportFileName="+stringpath);
    
      File sourceFile  =new File(stringpath);
      long start = System.currentTimeMillis();
    
      System.err.println("PDF creation time : " + (System.currentTimeMillis() - start));

      //下载
      response.reset();//
      response.setContentType("application/x-download");   
      String filedisplay = fileDownName+".pdf";
      filedisplay = URLEncoder.encode(filedisplay,"UTF-8");
      response.addHeader("Content-Disposition","attachment;filename=" + filedisplay);

      OutputStream outp = null;
    
      try
      {
          outp = response.getOutputStream();
      
           JasperExportManager.exportReportToPdfStream(jasperPrint, outp);
           
          outp.flush();
      }
      catch(Exception e)
      {
          System.out.println("Error!");
          e.printStackTrace();
      }
      finally
      {

          if(outp != null)
          {
              outp.close();
              outp = null;
          }
          //如下处理 getOutputStream() has already been called for this response 异常
      
          out.clear();
          out = pageContext.pushBody();
      }
%>

 其中：

LocationValueBeanFactory.getPageLoadTimeHistoryLineReportBeanCollection() 

为返回一个实体的数组的List：

 Arrays.asList( LocationValueBean [] data); 

 其中：

 JavaBeanListDataSoureFactory.createJasperPrintByJavaBeanList ()

代码为：

 //本类可能会用到的包：

 //

import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRExporterParameter;
import net.sf.jasperreports.engine.JRRuntimeException;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.export.JRHtmlExporter;
import net.sf.jasperreports.engine.export.JRHtmlExporterParameter;
import net.sf.jasperreports.j2ee.servlets.*;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
//

 //

       public static JasperPrint  createJasperPrintByJavaBeanList(String reportFileName,Map parameters,Collection collection)
        {
           
            String path = "";
            Properties prop = new Properties();
            try {
                InputStream in = JavaBeanListDataSoureFactory.class.getClassLoader().getResourceAsStream("report.properties");
                prop.load(in);
                path = prop.getProperty("site.reportjasper.path");
                in.close();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            JRHtmlExporter exporter = new JRHtmlExporter();
            JasperPrint jasperPrint = null;
             //PathClassPath classpath = new PathClassPath();
            //ReadConfigInfo conf = new ReadConfigInfo();
             String reportFileNameResult = path+reportFileName;
            File reportFile = new File(reportFileNameResult);
            if (!reportFile.exists())
                throw new JRRuntimeException("File "+reportFileName+" not found. The report design must be compiled first.");
            parameters.put("ReportTitle", "Address Report");
            parameters.put("BaseDir", reportFile.getParentFile());
            try {
                
                jasperPrint = 
                    JasperFillManager.fillReport(
                        reportFileNameResult, 
                        parameters, 
                        new JRBeanCollectionDataSource(collection)
                        );
                
            } catch (JRException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return jasperPrint;
        }

PS:博客园中的插入代码依然有问题啊，有的时候最上面一行会从代码块中跑出来，有的时候最下面一行会跑出来，我的环境：Win7 x64+Chrome 21.01180.89