JasperReports - 填写报告

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

报告填写过程所需的主要输入是 −

  • 报告模板 − 这是实际的 JasperReport 文件。

  • 报告参数 − 这些基本上是在报告填写时传递给引擎的命名值。我们将在报告参数一章中讨论它们。

  • 数据源 −我们可以从一系列数据源(如 SQL 查询、XML 文件、csv 文件、HQL(Hibernate 查询语言)查询、Java Bean 集合等)填充 Jasper 文件。这将在报告数据源一章中详细讨论。

此过程生成的输出是 .jrprint 文档,可供查看、打印或导出为其他格式。外观类 net.sf.jasperreports.engine.JasperFillManager 通常用于用数据填充报告模板。该类有各种 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提供)。

该外观类中有两类 fillReportXXX() 方法 −

  • 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,报告都是用关系数据库中的数据填充的。这是通过 − 实现的

    • 通过 JDBC 连接到数据库。

    • 在报告模板中包含 SQL 查询。

    • JasperReports 引擎使用传入的连接并执行 SQL 查询。

    • 这样就生成了一个报告数据源,用于填充报告。

  • 第二种,当需要填充的数据以其他形式提供时,接收 net.sf.jasperreports.engine.JRDataSource 对象。

填充报告模板

让我们编写一个报告模板。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 JasperReport Engine,以填充此编译报告。

编写一个 POJO DataBean.java,它表示数据对象 (Java bean)。此类定义两个 String 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;
   }
}

编写一个 DataBeanList.java 类,该类具有业务逻辑,用于生成 java bean 对象集合。这将进一步传递给 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;
   }
}

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

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();
      }
   }
}

生成报告

我们现在将使用常规 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 取自环境设置一章,应将其放在与 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>

接下来我们打开命令行窗口,进入build.xml所在的目录,最后执行命令ant -Dmain-class = com.tutorialspoint.JasperReportFill(executereport是默认目标),如下 −

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

上述执行的结果是在与 .jasper 文件相同的目录中生成一个文件 jasper_report_template.jrprint(在本例中,它生成在 C:\tools\jasperreports-5.0.1\test)。