Jasper Reports 简明教程

JasperReports - Exporting Reports

我们在上一章中看到了如何打印和查看 JasperReport 生成的文档。在这里，我们将看到如何将这些报告转换为 PDF、HTML 和 XLS 等其他格式或导出到这些格式。提供了 Facade 类 net.sf.jasperreports.engine.JasperExportManager 以实现此功能。导出是指将 JasperPrint 对象（.jrprint 文件）转换为不同的格式。

以下代码（JasperReportExport.java）演示了 JasperReport 文档的导出过程。JasperExportManager 仅提供将报告导出到 PDF、HTML 和 XML 的方法。为了导出到 XLS 格式，我们使用了类 net.sf.jasperreports.engine.export.JRXlsExporter。此代码生成以下三个文件−

  1. sample_report.pdf

  2. sample_report.html

  3. sample_report.xls

Exporting to Other Formats

我们来编写一个报告模板。JRXML文件（C:\tools\jasperreports-5.0.1\test\jasper_report_template.jrxml）的内容如下：

<?xml version = "1.0" encoding = "UTF-8"?>
<!DOCTYPE jasperReport PUBLIC "//JasperReports//DTD Report Design//EN"
   "http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">

<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 = "jasper_report_template" language = "groovy" pageWidth = "595"
   pageHeight = "842" columnWidth = "555" leftMargin = "20" rightMargin = "20"
   topMargin = "20" bottomMargin = "20">

   <queryString>
      <![CDATA[]]>
   </queryString>

   <field name = "country" class = "java.lang.String">
      <fieldDescription><![CDATA[country]]></fieldDescription>
   </field>

   <field name = "name" class = "java.lang.String">
      <fieldDescription><![CDATA[name]]></fieldDescription>
   </field>

   <columnHeader>
      <band height = "23">

         <staticText>
            <reportElement mode = "Opaque" x = "0" y = "3"
               width = "535" height = "15" backcolor = "#70A9A9" />

            <box>
               <bottomPen lineWidth = "1.0" lineColor = "#CCCCCC" />
            </box>

            <textElement />
            <text><![CDATA[]]> </text>
         </staticText>

         <staticText>
            <reportElement x = "414" y = "3" width = "121" height = "15" />

            <textElement textAlignment = "Center" verticalAlignment = "Middle">
               <font isBold = "true" />
            </textElement>

            <text><![CDATA[Country]]></text>
         </staticText>

         <staticText>
            <reportElement x = "0" y = "3" width = "136" height = "15" />

            <textElement textAlignment = "Center" verticalAlignment = "Middle">
               <font isBold = "true" />
            </textElement>

            <text><![CDATA[Name]]></text>
         </staticText>

      </band>
   </columnHeader>

   <detail>
      <band height = "16">

         <staticText>
            <reportElement mode = "Opaque" x = "0" y = "0"
               width = "535" height = "14" backcolor = "#E5ECF9" />

            <box>
               <bottomPen lineWidth = "0.25" lineColor = "#CCCCCC" />
            </box>

            <textElement />
            <text><![CDATA[]]> </text>
         </staticText>

         <textField>
            <reportElement x = "414" y = "0" width = "121" height = "15" />

            <textElement textAlignment = "Center" verticalAlignment = "Middle">
               <font size = "9" />
            </textElement>

            <textFieldExpression class = "java.lang.String">
               <![CDATA[$F{country}]]>
            </textFieldExpression>
         </textField>

         <textField>
            <reportElement x = "0" y = "0" width = "136" height = "15" />
            <textElement textAlignment = "Center" verticalAlignment = "Middle" />

            <textFieldExpression class = "java.lang.String">
               <![CDATA[$F{name}]]>
            </textFieldExpression>
         </textField>

      </band>
   </detail>

</jasperReport>

接下来， C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint\DataBean.java POJO 文件内容如下所示−

package com.tutorialspoint;

public class DataBean {
   private String name;
   private String country;

   public String getName() {
      return name;
   }

   public void setName(String name) {
      this.name = name;
   }

   public String getCountry() {
      return country;
   }

   public void setCountry(String country) {
      this.country = country;
   }
}

文件 *C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint\DataBeanList.java * 的内容如下所示−

package com.tutorialspoint;

import java.util.ArrayList;

public class DataBeanList {
   public ArrayList<DataBean> getDataBeanList() {
      ArrayList<DataBean> dataBeanList = new ArrayList<DataBean>();

      dataBeanList.add(produce("Manisha", "India"));
      dataBeanList.add(produce("Dennis Ritchie", "USA"));
      dataBeanList.add(produce("V.Anand", "India"));
      dataBeanList.add(produce("Shrinath", "California"));

      return dataBeanList;
   }

   /**
    * This method returns a DataBean object,
    * with name and country set in it.
    */
   private DataBean produce(String name, String country) {
      DataBean dataBean = new DataBean();
      dataBean.setName(name);
      dataBean.setCountry(country);

      return dataBean;
   }
}

写一个 JasperReportFill.java 主类文件，从类 (DataBeanList) 中获取 Java Bean 集合，并将其传递给 JasperReports 引擎以填充报告模板。将其保存到 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 目录。

package com.tutorialspoint;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRExporterParameter;
import net.sf.jasperreports.engine.JasperExportManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.export.JRXlsExporter;

public class JasperReportFill {
   @SuppressWarnings("unchecked")
   public static void main(String[] args) {
      String sourceFileName = "c://tools/jasperreports-5.0.1/"
         + "test/jasper_report_template.jasper";
      String printFileName = null;
      DataBeanList DataBeanList = new DataBeanList();
      ArrayList<DataBean> dataList = DataBeanList.getDataBeanList();
      JRBeanCollectionDataSource beanColDataSource =
         new JRBeanCollectionDataSource(dataList);

      Map parameters = new HashMap();
      try {
         printFileName = JasperFillManager.fillReportToFile(sourceFileName,
            parameters, beanColDataSource);
         if (printFileName != null) {
            /**
             * 1- export to PDF
             */
            JasperExportManager.exportReportToPdfFile(printFileName,
               "C://sample_report.pdf");

            /**
             * 2- export to HTML
             */
            JasperExportManager.exportReportToHtmlFile(printFileName,
               "C://sample_report.html");

            /**
             * 3- export to Excel sheet
             */
            JRXlsExporter exporter = new JRXlsExporter();

            exporter.setParameter(JRExporterParameter.INPUT_FILE_NAME,
               printFileName);
            exporter.setParameter(JRExporterParameter.OUTPUT_FILE_NAME,
               "C://sample_report.xls");

            exporter.exportReport();
         }
      } catch (JRException e) {
         e.printStackTrace();
      }
   }
}

在这里，我们包含了将 jasper 打印文件导出到 pdf、html 和 xls 格式的逻辑。

Generating Reports

让我们使用常规 ANT 构建过程编译并执行上述文件。build.xml 文件如下所示−

<?xml version = "1.0" encoding = "UTF-8"?>
<project name = "JasperReportTest" default = "executereport" basedir = ".">
   <import file = "baseBuild.xml"/>

   <target name = "executereport" depends = "compile,compilereportdesing,run">
      <echo message = "Im here"/>
   </target>

   <target name = "compilereportdesing" description = "Compiles the JXML file and
      produces the .jasper file.">

      <taskdef name = "jrc"
         classname = "net.sf.jasperreports.ant.JRAntCompileTask">
         <classpath refid = "classpath" />
      </taskdef>

      <jrc destdir = ".">
         <src>
            <fileset dir = ".">
               <include name = "*.jrxml" />
            </fileset>
         </src>
         <classpath refid = "classpath" />
      </jrc>

   </target>

</project>

转到命令提示符，然后转到放置 build.xml 的目录 C:\tools\jasperreports-5.0.1\test。最后，执行命令 ant -Dmain-class=com.tutorialspoint.JasperReportFill 。输出如下所示−

C:\tools\jasperreports-5.0.1\test>ant -Dmain-class=com.tutorialspoint.JasperReportFill
Buildfile: C:\tools\jasperreports-5.0.1\test\build.xml

clean-sample:
   [delete] Deleting directory C:\tools\jasperreports-5.0.1\test\classes
   [delete] Deleting: C:\tools\jasperreports-5.0.1\test\jasper_report_template.jasper
   [delete] Deleting: C:\tools\jasperreports-5.0.1\test\jasper_report_template.jrprint

compile:
   [mkdir] Created dir: C:\tools\jasperreports-5.0.1\test\classes
   [javac] C:\tools\jasperreports-5.0.1\test\baseBuild.xml:28:
   warning: 'includeantruntime' was not set, defaulting t
   [javac] Compiling 4 source files to C:\tools\jasperreports-5.0.1\test\classes

compilereportdesing:
   [jrc] Compiling 1 report design files.
   [jrc] log4j:WARN No appenders could be found for logger
   (net.sf.jasperreports.engine.xml.JRXmlDigesterFactory).
   [jrc] log4j:WARN Please initialize the log4j system properly.
   [jrc] log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
   [jrc] File : C:\tools\jasperreports-5.0.1\test\jasper_report_template.jrxml ... OK.

run:
   [echo] Runnin class : com.tutorialspoint.JasperReportFill
   [java] log4j:WARN No appenders could be found for logger
   (net.sf.jasperreports.extensions.ExtensionsEnvironment).
   [java] log4j:WARN Please initialize the log4j system properly.

executereport:
   [echo] Im here

BUILD SUCCESSFUL
Total time: 32 seconds

作为上述执行的结果，你将在 C:\ 目录中找到三个文件 sample_report.pdf、sample_report.html、sample_report.xls。