昨天给大家讲了一种方式，今天换一种方式，就是说，将主报表的某一参数直接传递给子报表作为数据源，当然，这个参数是包含子报表的，这个主要是基于Web开发，也是从网友那边拿来的，结合自己的经验再做一遍。
首先创建我们需要的JavaBean
ProvinceBean.java
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package test;
import java.util.ArrayList;
public class ProvinceBean
{
private String provinceName;
private ArrayList cities;
public String getProvinceName()
{
return provinceName;
}
public void setProvinceName(String provinceName)
{
this.provinceName = provinceName;
}
public ArrayList getCities()
{
return cities;
}
public void setCities(ArrayList cities)
{
this.cities = cities;
}
}
CityBean,java
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package test;
public class CityBean
{
private String cityName;
public String getCityName()
{
return cityName;
}
public void setCityName(String cityName)
{
this.cityName = cityName;
}
}
注意一下，这里Province是主表的元素其中他包含了cityBean，那么显然CityBean要作为子表之中的元素
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下面创建Servlet类这个类我“本地化”一下，改动了一点
package test;
import java.io.IOException;
import java.io.OutputStream;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.sun.net.ssl.internal.ssl.Debug;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JRExporterParameter;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.export.JRPdfExporter;
import net.sf.jasperreports.engine.util.JRLoader;
public class ChildReportServlet extends HttpServlet
{
private static final long serialVersionUID = -1233414483047719876L;
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException
{
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException
{
try
{
String root_path = this.getServletContext().getRealPath("/");
root_path = root_path.replace('\\', '/');
String reportFilePath = root_path + "ireport/parent_sub.jasper";
//Debug.println(reportFilePath, root_path);
JRDataSource dataSource = this.createDataSource();
Map parameters = new HashMap();
parameters.put("SUBREPORT_DIR", root_path + "ireport/");
JasperReport report = (JasperReport)JRLoader.loadObject(reportFilePath);
JasperPrint jasperPrint = JasperFillManager.fillReport(report, parameters, dataSource);
OutputStream ouputStream = resp.getOutputStream();
resp.setContentType("application/pdf");
resp.setCharacterEncoding("UTF-8");
resp.setHeader("Content-Disposition", "attachment; filename=\"" +URLEncoder.encode("PDF报表", "UTF-8")+ ".pdf\"");
// 使用JRPdfExproter导出器导出pdf
JRPdfExporter exporter = new JRPdfExporter();
exporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint);
exporter.setParameter(JRExporterParameter.OUTPUT_STREAM, ouputStream);
exporter.exportReport();
ouputStream.close();
}catch(Exception ex)
{
ex.printStackTrace();
}
}
private JR