Jasper Reports 简明教程

JasperReports - Filling Reports

任何报告工具的主要目的是生成高质量的文档。报告填充过程通过处理数据集来帮助报告工具实现此目的。

报告填充过程所需的主要输入如下：

  1. Report Template −这是实际的JasperReport文件。

  2. Report Parameters −这些基本上是在报告填充时传递给引擎的命名值。我们将在 Report Parameter 章节中讨论它们。

  3. Data Source −我们可以从一系列数据源填充Jasper文件，如SQL查询、XML文件、csv文件、HQL（Hibernate查询语言）查询、Java Bean集合等。这将在 Report Data Sources 章节中详细讨论。

此过程生成的输出是一个*.jrprint*文档，可以查看、打印或导出为其他格式。外观类net.sf.jasperreports.engine.JasperFillManager通常用于使用数据填充报告模板。此类有各种fillReportXXX()方法，用于填充报告模板（模板可以位于磁盘上、从输入流中选取或直接作为内存中提供）。

此外观类中有两类fillReportXXX()方法：

  1. 第一种类型接收java.sql.Connection对象作为第三个参数。大多数情况下，报告使用关系数据库中的数据进行填充。这是通过以下方式实现的：通过JDBC连接到数据库。在报告模板中包含一个SQL查询。JasperReports引擎使用传入的连接并执行SQL查询。因此生成了用于填充报告的报告数据源。

  2. 第二种类型接收net.sf.jasperreports.engine.JRDataSource对象，而需要填充的数据以其他形式存在时。

Filling Report Templates

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，我们向JasperReport引擎传递Java数据对象（Java bean）集合，以填充此已编译的报告。

编写POJO DataBean.java，它表示数据对象（Java bean）。此类定义了两个字符串对象，即“name”和“country”。将其保存到目录 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 。

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;
   }
}

编写类DataBeanList.java，它具有生成Java bean对象集合的业务逻辑。将其进一步传递给JasperReports引擎以生成报告。这里我们在列表中添加了4个DataBean对象。将其保存到目录 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint 。

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();
      }
   }
}

Generating Reports

现在，我们将使用常规 ANT 构建过程编译并执行这些文件。build.xml 文件如下所示 -

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 = "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，让我们打开命令行窗口并转到放置 build.xml 的目录。最后，执行以下命令 * ant -Dmain-class = com.tutorialspoint.JasperReportFill* ( executereport 是默认目标) -

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

compile:
   [javac] C:\tools\jasperreports-5.0.1\test\baseBuild.xml:27:
   warning: 'includeantruntime' was not set, defaulting to
   build.sysclasspath=last; set to false for repeatable builds
   [javac] Compiling 1 source file to
   C:\tools\jasperreports-5.0.1\test\classes

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.

BUILD SUCCESSFUL
Total time: 8 seconds

通过上述执行操作，可生成 jasper_report_template.jrprint 文件，且该文件与 .jasper 文件放在同一目录中（在此例中，该文件生成在 C:\tools\jasperreports-5.0.1\test 中）。