jasperreport 使用子報表(使用JavaBean集合作為資料來源)
程式部分
第一步，建立與之相關的Bean類，如下所示：
ProvinceBean.java
package lld.test.ireport;
import java.util.ArrayList;
public class ProvinceBean
{
private String provinceName;
private ArrayList<CityBean> cities;
public String getProvinceName()
{
return provinceName;
}
public void setProvinceName(String provinceName)
{
this.provinceName = provinceName;
}
public ArrayList<CityBean> getCities()
{
return cities;
}
public void setCities(ArrayList<CityBean> cities)
{
this.cities = cities;
}
}
CityBean.java
package lld.test.ireport;
public class CityBean
{
private String cityName;
public String getCityName()
{
return cityName;
}
public void setCityName(String cityName)
{
this.cityName = cityName;
}
}
第二步 建立Servlet類，如下所示
package lld.test.ireport;
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 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 + "WEB-INF/classes/lld/test/ireport/child_report_jbs_parent.jasper";
JRDataSource dataSource = this.createDataSource();
Map<String, String> parameters = new HashMap<String, String>();
parameters.put("SUBREPORT_DIR", root_path + "WEB-INF/classes/lld/test/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報表", "UTF-8") + ".pdf/"");
// 使用JRPdfExproter匯出器匯出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 JRDataSource createDataSource()
{
//生成測試資料
ArrayList<ProvinceBean> provinces = new ArrayList<ProvinceBean>();
ProvinceBean province = new ProvinceBean();
province.setProvinceName("山東");
ArrayList<CityBean> cities = new ArrayList<CityBean>();
CityBean city = new CityBean();
city.setCityName("濟南");
cities.add(city);
city = new CityBean();
city.setCityName("青島");
cities.add(city);
city = new CityBean();
city.setCityName("濰坊");
cities.add(city);
province.setCities(cities);
provinces.add(province);
province = new ProvinceBean();
province.setProvinceName("江蘇");
cities = new ArrayList<CityBean>();
city = new CityBean();
city.setCityName("南京");
cities.add(city);
city = new CityBean();
city.setCityName("無錫");
cities.add(city);
city = new CityBean();
city.setCityName("蘇州");
cities.add(city);
province.setCities(cities);
provinces.add(province);
return new JRBeanCollectionDataSource(provinces);
}
}
如果有了以前例子的基礎，這個例子應該不難看懂，需要注意的是下面這4行程式碼，這是新出現的特性：
Map<String, String> parameters = new HashMap<String, String>();
parameters.put("SUBREPORT_DIR", root_path + "WEB-INF/classes/lld/test/ireport/");
JasperReport report = (JasperReport)JRLoader.loadObject(reportFilePath);
JasperPrint jasperPrint = JasperFillManager.fillReport(report, parameters, dataSource);
這是因為，在使用子報表時，需要一個SUBREPORT_DIR變數，指示子報表所在的路徑，在下面建立子報表的相關部分會再次進行描述，請注意對比。我在以前的例子中，呼叫JasperFillManager.fillReport()方法時第二個引數均為null，實際上，這個引數可傳遞到jasper report中的Parameters項中。
注意：如果使用了servlet 使用了SUBREPORT_DIR變數 ，那麼在主報表中指定子報表的路徑就可以為空，如果不為空也不會報錯。
如：
<parameter name="SUBREPORT_DIR" class="java.lang.String" isForPrompting="false">
<defaultValueExpression><![CDATA[]]></defaultValueExpression>
</parameter>
建立報表
第一步，建立主報表，如下圖所示
主報表Connection設定如下圖所示：
點選main前面的那個按鈕。出現：
取一個名字叫main, 工廠類如下：
package com.dnion.dayu.jasper;
import java.util.ArrayList;
import java.util.Collection;
public class WorkflowBeanFactory
{
public static Collection getBeanCollection()
{
ArrayList<ProvinceBean> provinces = new ArrayList<ProvinceBean>();
ProvinceBean province = new ProvinceBean();
province.setProvinceName("山東1");
ArrayList<CityBean> cities = new ArrayList<CityBean>();
CityBean city = new CityBean();
city.setCityName("濟南");
cities.add(city);
city = new CityBean();
city.setCityName("青島");
cities.add(city);
city = new CityBean();
city.setCityName("濰坊");
cities.add(city);
province.setCities(cities);
provinces.add(province);
province = new ProvinceBean();
province.setProvinceName("江蘇");
cities = new ArrayList<CityBean>();
city = new CityBean();
city.setCityName("南京");
cities.add(city);
city = new CityBean();
city.setCityName("無錫");
cities.add(city);
city = new CityBean();
city.setCityName("蘇州");
cities.add(city);
province.setCities(cities);
provinces.add(province);
return provinces ;
}
}
注意：1.在這裡如裡指定了工廠方法，那麼在iReport裡可以直接預覽出資料。
2.如果不在這裡指定工廠方法，那麼就在servlet把這個方法傳過來，方法可以直接寫在servlet裡，而且不要是static方法。
classpath :
選單欄：工具---->選項--->出現介面如下圖：點選Add Folder,選擇編譯後的bean所在的檔案，一定是class檔案
其DataSource設定如下圖所示
點選preview右邊的圖示，出現report query 如下圖：輸入 主報表bean路徑，點選 ：Red attriutes
下面的大框出現bean類的屬性：provinceName,cities,
選中兩個引數，點選 Add select field(s) ,最下面的框出現這兩個引數，好了，點選OK就行了。
第二步，建立子報表，建立一個新的報表，取名叫sub, 在主報表中引用子報表，可使用工具欄的“SubReport”圖示直接建立，選擇已經存在的報表（use an existing report），在這裡選擇sub，利用系統的wizard一步一步設定，
子報表我們使用CityBean做為資料來源,選擇use a JRDatasource expression ,“new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource($F{cities})”，下一步，下一步完成