iReport 笔记(六) 使用子报表(使用JavaBean集合作为数据源)

p {
font-family: "宋体";
font-size: 12px;
font-style: normal;
line-height: 18px;
font-weight: normal;
text-indent: 24px;
}
h1 {
font-size: 36px;
font-style: normal;
font-weight: bold;
text-decoration: underline;
color: #990000;
text-align: center;
}
h2 {
font-size: 24px;
font-weight: bold;
color: #9900FF;
}
h3 {
font-size: 18px;
font-weight: bold;
color: #000099;
}
a {
color: #660033;
text-decoration: none;
}
img {
vertical-align: middle;
}
ul {
font-family: "宋体";
font-size: 12px;
line-height: 18px;
}
PRE {
font-size: 12px;
padding: 5px;
border-style: solid;
border-width: 1px;
border-color: #CCCCCC;
background-color: #F0F0F0;
}

table {
font-size: 12px;
border-collapse: collapse;
}
tr {
background-color: inherit;
color: black;
padding: 5px;
text-align: left;
border: 1px solid #999999;
}
th {
text-align: center;
background-color: #cccccc;
color: black;
font-weight: bolder;
padding: 5px;
border: 1px solid #999999;
}
td {
border: 1px solid #999999;
padding: 5px;
}

ol {
font-family: "宋体";
font-size: 12px;
line-height: 18px;
}
h4 {
font-size: 16px;
}

6 子报表

在本例中，我使用子报表将生成如下样式的报表

6.1 程序部分

第一步，创建与之相关的Bean类，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 创建Servlet类，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 JRDataSource createDataSource()
{
//生成测试数据
ArrayList<ProvinceBean> provinces = new ArrayList<ProvinceBean>();

ProvinceBean province = new ProvinceBean();
province.setProvinceName("山东");

ArrayList<CityBean> cities = new ArrayList<CityBean>();
CityBean city = new CityBean();
city.setCityName("济南");
cities.add(city);
city = new CityBean();
city.setCityName("青岛");
cities.add(city);
city = new CityBean();
city.setCityName("潍坊");
cities.add(city);

province.setCities(cities);
provinces.add(province);

province = new ProvinceBean();
province.setProvinceName("江苏");

cities = new ArrayList<CityBean>();
city = new CityBean();
city.setCityName("南京");
cities.add(city);
city = new CityBean();
city.setCityName("无锡");
cities.add(city);
city = new CityBean();
city.setCityName("苏州");
cities.add(city);

province.setCities(cities);
provinces.add(province);

return new JRBeanCollectionDataSource(provinces);
}

}

如果有了以前例子的基础，这个例子应该不难看懂，需要注意的是下面这4行代码，这是新出现的特性：

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);

这是因为，在使用子报表时，需要一个SUBREPORT_DIR变量，指示子报表所在的路径，在下面创建子报表的相关部分会再次进行描述，请注意对比。我在以前的例子中，调用JasperFillManager.fillReport()方法时第二个参数均为null，实际上，这个参数可传递到jasper report中的Parameters项中。

6.2 创建报表

第一步，创建主报表，如下图所示



其Connection设置如下图所示：



其DataSource设置如下图所示



第二步，创建子报表，可使用工具栏的“SubReport”图标直接创建，使用默认的名称，并确定好子报表的位置，利用系统的wizard一步一步设置，注意在第2步设置”Connection/Datasource ”时最好选择”no connection or datasource”)

子报表我们使用CityBean做为数据源，设置方法参考上一步

第三步，在父报表中设置子报表控件的属性，在SubReport面板中设置其“Connection/Data Source Expression”为“new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource($F{cities})”，如下图所示：



第四步，编译，将编译生成的.jasper文件放置到项目的相应目录中

注: 如需本例源代码, 请留言