Jasper Reports 简明教程

Jasper Report - View & Print Reports

报告填充过程 JasperPrint 对象的输出可以使用内置查看器组件查看，或打印，或导出为更流行的文档格式，如 PDF、HTML、RTF、XLS、ODT、CSV 或 XML。本章将讨论 Jasper 文档的查看和打印，下一章（即 'Export Reports.' ）将讨论导出。

Viewing Reports

JasperReport 提供了一个内置查看器，用于以其原始格式查看生成的报告。它是一个基于 swing 的组件，其他 Java 应用程序可以集成此组件，而无需将文档导出为其他格式以便查看或打印。net.sf.jasperreports.view.JRViewer 类表示此可视组件。此类也可以通过对其进行子类化根据应用程序需要进行定制。

JasperReports 还具有一个 Swing 应用程序，它使用可视组件来查看报告。此应用程序有助于以 *.jrprint 生成的相同格式查看报告。此 Swing 应用程序在类 net.sf.jasperreports.view.JasperViewer 中实现。要使用此类查看报告，我们需要将其包装到 ANT 目标中。

Viewing the generated Report

以下示例演示了如何使用 JasperViewer 类查看报告 -

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，让我们将 Java 数据对象（Java Bean）集合传递给 JasperReports 引擎，以填充此已编译的报告。

编写一个代表数据对象（Java bean）的 POJO DataBean.java。此类定义两个字符串对象，即“name”和“country”。将其保存到 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 目录。

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;
   }
}

编写一个具有业务逻辑以生成 Java bean 对象集合的类 DataBeanList.java。将其进一步传递到 JasperReports 引擎以生成报告。在此，我们正在 List 中添加 4 个 DataBean 对象。将其保存到 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 目录。

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.JasperFillManager;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;

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

      JRBeanCollectionDataSource beanColDataSource = new
         JRBeanCollectionDataSource(dataList);

      Map parameters = new HashMap();
      try {
         JasperFillManager.fillReportToFile(
            sourceFileName, parameters, beanColDataSource);
      } catch (JRException e) {
         e.printStackTrace();
      }
   }
}

让我们向 build.xml 文件编写一个目标 viewFillReport 。build.xml 文件如下 -

导入文件 - baseBuild.xml 从第 Environment Setup 章节中选取，且应放置在与 build.xml 相同的目录中。

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

   <target name = "viewFillReport" depends = "compile,compilereportdesing,run"
      description = "Launches the report viewer
      to preview the report stored in the .JRprint file.">

      <java classname = "net.sf.jasperreports.view.JasperViewer" fork = "true">
         <arg value = "-F${file.name}.JRprint" />
         <classpath refid = "classpath" />
      </java>
   </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>

接下来，让我们打开命令行窗口，并转到放置 build.xml 的目录。最后，执行命令 * ant -Dmain-class=com.tutorialspoint.JasperReportFill*（viewFillReport 是默认目标）。结果，我们看到一个 JasperViewer 窗口，如下面的屏幕截图所示 -

jasper report viewer

Printing Reports

我们可以使用 net.sf.jasperreports.engine.JasperPrintManager 类打印由 JasperReports 库生成的文档（以其专有格式即 JasperPrint 对象）。这是一个依赖 Java 2 Printing API 的外壳类。一旦 JasperReport 文档导出到其他格式（如 HTML 或 PDF），我们还可以打印文档。

Printing the Generated Report

以下代码演示了打印报告。让我们更新我们现有的类 JasperReportFill。我们将使用 JasperPrintManager.printReport（）方法。该方法将源文件名（在此，我们传递.jrprint 文件，这是我们使用 JasperFillManager.fillReportToFile() 方法在上一步中生成的）作为第一个参数。第二个参数是用于显示标准打印对话框的布尔值（我们在此将其设置为 true ）。

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.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrintManager;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;

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){
            JasperPrintManager.printReport( printFileName, true);
         }
      } catch (JRException e) {
         e.printStackTrace();
      }
   }
}

现在，让我们将此文件保存到目录 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 。我们将使用 ANT 编译并执行此文件。build.xml 的内容如下 -

<?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>

接下来，让我们打开命令提示符并转到放置 build.xml 的目录。最后，执行命令 ant -Dmain-class=com.tutorialspoint.JasperReportPrint 。结果，会出现一个打印对话框。单击确定以打印文档。