开发者使用JasperReport——不同数据源之XML和CSV数据源
前言
上一篇我们讲解了实体对象数据源，一个很实用的功能。但是有时候我们会用这样的需求，有一个xml或者cvs文件，我们需要将它展现成报表形式，这个实现很简单，今天就来讲解JRXmlDataSource。
正题
跟之前的一样，我们要生成报表需要以下几个步骤：
1.引入jar包，请看《静态文本报表》 。
2.新建报表模版：
为了能够让我们的报表顺利的生成，我们需要对报表模版做一个小更改，在字段标签里面添加<fieldDescription>标签。
<?xml version="1.0" encoding="UTF-8"?>
<jasperReport xmlns="http://jasperreports.sourceforge.net/jasperreports"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports http://jasperreports.sourceforge.net/xsd/jasperreport.xsd"
name="AircraftReportWithDescription">
<field name="ID" class="java.lang.String" >
<fieldDescription>
<![CDATA[ID]]>
</fieldDescription>
</field>
<field name="NAME" class="java.lang.String">
<fieldDescription>
<![CDATA[NAME]]>
</fieldDescription>
</field>
<field name="SEX" class="java.lang.String" >
<fieldDescription>
<![CDATA[SEX]]>
</fieldDescription>
</field>
<pageHeader>
<band height="30">
<staticText>
<reportElement x="0" y="0" width="69" height="24" />
<textElement verticalAlignment="Bottom"/>
<text>Id</text>
</staticText>
<staticText>
<reportElement x="140" y="0" width="79" height="24" />
<text>Name</text>
</staticText>
<staticText>
<reportElement x="280" y="0" width="69" height="24" />
<text>Sex</text>
</staticText>
</band>
</pageHeader>
<detail>
<band height="40">
<textField>
<reportElement x="0" y="0" width="69" height="24" />
<textFieldExpression class="java.lang.String">
$F{ID}
</textFieldExpression>
</textField>
<textField>
<reportElement x="140" y="0" width="69" height="24" />
<textFieldExpression class="java.lang.String">
$F{NAME}
</textFieldExpression>
</textField>
<textField>
<reportElement x="280" y="0" width="69" height="24" />
<textFieldExpression class="java.lang.String">
$F{SEX}
</textFieldExpression>
</textField>
</band>
</detail>
</jasperReport>
3.编译报表模版，请看《静态文本报表》。
4.编写xml、csv文件：
对于xml文件我们没有限制，只要是符合xml标签格式要求的即可。
1）我们新建一个AircraftData.xml：
<?xml version="1.0" encoding="UTF-8"?> <AircraftData> <aircraft> <ID>1</ID> <NAME>REBECCA1</NAME> <SEX>FEMALE</SEX> </aircraft> <aircraft> <ID>2</ID> <NAME>REBECCA2</NAME> <SEX>FEMALE</SEX> </aircraft> <aircraft> <ID>3</ID> <NAME>REBECCA3</NAME> <SEX>FEMALE</SEX> </aircraft> <aircraft> <ID>4</ID> <NAME>REBECCA4</NAME> <SEX>FEMALE</SEX> </aircraft> </AircraftData>
2）再来建一个AircraftCsv.csv文件
ID,NAME,SEX 1,Rebecca1,female 2,Rebecca2,female 3,Rebecca3,female 4,Rebecca4,female 5,Rebecca5,female 6,Rebecca6,female 7,Rebecca7,female 8,Rebecca8,female
5.编写servlet:
1）读取xml文件的XmlDSReportServlet ：
package com.dan.servlet;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.HashMap;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jasperreports.engine.JasperRunManager;
import net.sf.jasperreports.engine.data.JRXmlDataSource;
/**
* 使用JRXmlDataSource 填充
* @author zdd
*
*/
public class XmlDSReportServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 2174316885912562306L;
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
ServletOutputStream servletOutputStream = resp.getOutputStream();
InputStream reportStream = getServletConfig().getServletContext().getResourceAsStream("/WEB-INF/classes/reports/AircraftReportWithDescription.jasper");
try{
JRXmlDataSource xmlDataSource = new JRXmlDataSource(new BufferedInputStream(getServletConfig().getServletContext().getResourceAsStream("/WEB-INF/classes/reports/AircraftData.xml")),"/AircraftData/aircraft");
JasperRunManager.runReportToPdfStream(reportStream, servletOutputStream, new HashMap(),xmlDataSource);
servletOutputStream.flush();
servletOutputStream.close();
}catch(Exception e){
StringWriter stringWriter = new StringWriter();
PrintWriter printWriter = new PrintWriter(stringWriter);
e.printStackTrace(printWriter);
resp.setContentType("text/plain");
resp.getOutputStream().print(stringWriter.toString());
}
}
}
2）读取csv文件的CsvDSReportServlet ：
package com.dan.servlet;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.HashMap;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jasperreports.engine.JasperRunManager;
import net.sf.jasperreports.engine.data.JRCsvDataSource;
/**
* 使用JRResultSetDataSource填充
* @author zdd
*
*/
public class CsvDSReportServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 2174316885912562306L;
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
ServletOutputStream servletOutputStream = resp.getOutputStream();
InputStream reportStream = getServletConfig().getServletContext().getResourceAsStream("/WEB-INF/classes/reports/AircraftReportWithDescription.jasper");
try{
JRCsvDataSource jRCsvDataSource = new JRCsvDataSource(new InputStreamReader(getServletConfig().getServletContext().getResourceAsStream("/WEB-INF/classes/reports/AircraftCsv.csv")));
jRCsvDataSource.setUseFirstRowAsHeader(true);
JasperRunManager.runReportToPdfStream(reportStream, servletOutputStream, new HashMap(),jRCsvDataSource);
resp.setContentType("application/pdf");
servletOutputStream.flush();
servletOutputStream.close();
}catch(Exception e){
StringWriter stringWriter = new StringWriter();
PrintWriter printWriter = new PrintWriter(stringWriter);
e.printStackTrace(printWriter);
resp.setContentType("text/plain");
resp.getOutputStream().print(stringWriter.toString());
}
}
}
5.配置web.xml，就是配置servlet
6.运行项目
看一下我的运行结果：
1）读取xml文件：
2）读取csv文件：
小结：
xml和csv文件是我们经常见到的两种数据文件格式，JasperReport将其单独拿出来也说明了这点，其他形式的数据源还会继续给大家进行更新。
