- JasperReports 教程
- JasperReports - 主页
- JasperReports - 入门
- JasperReports - 环境设置
- JasperReports - 生命周期
- JasperReports - 设计
- JasperReports - 编译设计
- JasperReports - 填充
- JasperReports - 查看和打印
- JasperReports - 导出
- JasperReports - 参数
- JasperReports - 数据源
- JasperReports - 字段
- JasperReports - 表达式
- JasperReports - 变量
- JasperReports - 部分
- JasperReports - 组
- JasperReports - 字体
- JasperReports - Unicode 支持
- JasperReports - 样式
- JasperReports - Scriptlet
- JasperReports - 创建子报表
- JasperReports - 创建图表
- JasperReports - 交叉表
- JasperReports - 国际化
- JasperReports 资源
- JasperReports - 快速指南
- JasperReports - 有用的资源
- JasperReports - 讨论
创建子报表
子报表是 JasperReports 的优秀功能之一。此功能允许将一个报表合并到另一个报表中，即一个报表可以是另一个报表的子报表。子报表帮助我们保持报表设计简单，因为我们可以创建许多简单的报表并将它们封装到主报表中。子报表的编译和填写与普通报表一样。当合并到另一个报告模板中时，任何报告模板都可以用作子报告，而无需在（报告模板的）内部进行任何更改。
子报表就像普通的报表模板。它们实际上是net.sf.jasperreports.engine.JasperReport对象，是编译net.sf.jasperreports.engine.design.JasperDesign 对象后得到的。
<子报表>元素
将子报表引入主报表时使用 <subreport> 元素。以下是 <subreport> JRXML 元素中的子元素列表。
<报告元素>
<parametersMapExpression> - 用于将包含报表参数的映射传递到子报表。地图通常是从主报表中的参数获取的，或者使用内置的 REPORTS_PARAMETERS_MAP 参数将父报表的参数传递给子报表。该表达式应始终返回一个java.util.Map对象，其中键是参数名称。
<subreportParameter> - 该元素用于将参数传递给子报表。它有一个属性name，这是强制性的。
<connectionExpression> - 用于将java.sql.Connection传递到子报表。仅当子报表模板在报表填充阶段需要数据库连接时使用。
<dataSourceExpression> - 用于将数据源传递到子报表。该数据源通常从主报表中的参数获取，或者使用内置 REPORT_DATA_SOURCE 参数将父报表的数据源传递给子报表。
元素（connectionExpression 和 dataSourceExpression）不能同时出现在 <subreport> 元素声明中。这是因为我们无法同时提供数据源和子报表的连接。我们必须决定其中之一并坚持下去。
<returnValue> - 用于将子报表变量之一的值分配给主报表变量之一。该子元素具有如下属性 -
subreportVariable - 此属性指定要返回其值的子报表变量的名称。
toVariable - 此属性指定父报表变量的名称，其值将随子报表中的值复制/递增。
计算- 该属性可以采用以下值：Nothing、Count、DistinctCount、Sum、Average、Lowest、Highest、StandardDeviation、Variance。属性计算的默认值为“Nothing”。
incrementerFactoryClass - 此属性指定用于创建增量器实例的工厂类。
<subreportExpression> - 这指示在哪里可以找到子报表的已编译报表模板。该元素有一个类属性。class属性可以采用以下任意值：java.lang.String、java.io.File、java.net.URL、java.io.InputStream、net.sf.jasperreports.engine.JasperReport 。默认值为java.lang.String。
isUsingCache - 这是 <subreport> 元素的属性。这是一个布尔值，当设置为true时，报表引擎将尝试使用其指定的源来识别先前加载的子报表模板对象。此缓存功能仅适用于具有返回 java.lang.String 对象作为子报表模板源（表示文件名、URL 或类路径资源）的表达式的子报表元素。
例子
让我们举一个简单的例子来演示使用 JRDataSource 创建子报表。我们首先编写两个新的报告模板，一个是子报告，另一个是主报告。子报告（address_report_template.jrxml）模板的内容如下所示。将其保存到 C:\tools\jasperreports-5.0.1\test 目录。
<?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 = "address_report_template" pageWidth = "175" pageHeight = "842"
columnWidth = "175" leftMargin = "0" rightMargin = "0"
topMargin = "0" bottomMargin = "0">
<field name = "city" class = "java.lang.String"/>
<field name = "street" class = "java.lang.String"/>
<background>
<band splitType = "Stretch"/>
</background>
<title>
<band height = "20" splitType = "Stretch">
<staticText>
<reportElement x = "0" y = "0" width = "100" height = "20"/>
<textElement>
<font size = "14" isBold = "true"/>
</textElement>
<text><![CDATA[Addresses]]></text>
</staticText>
</band>
</title>
<pageHeader>
<band height = "12" splitType = "Stretch"/>
</pageHeader>
<columnHeader>
<band height = "12" splitType = "Stretch"/>
</columnHeader>
<detail>
<band height = "27" splitType = "Stretch">
<textField>
<reportElement x = "0" y = "0" width = "120" height = "20"/>
<textElement>
<font size = "12" isBold = "true"/>
</textElement>
<textFieldExpression class = "java.lang.String">
<![CDATA[$F{city}+" Address:"]]>
</textFieldExpression>
</textField>
<textField isStretchWithOverflow = "true">
<reportElement x = "120" y = "0" width = "435" height = "20"/>
<textElement>
<font size = "12"/>
</textElement>
<textFieldExpression class = "java.lang.String">
<![CDATA[$F{street}]]>
</textFieldExpression>
</textField>
</band>
</detail>
<columnFooter>
<band height = "8" splitType = "Stretch"/>
</columnFooter>
<pageFooter>
<band height = "11" splitType = "Stretch"/>
</pageFooter>
<summary>
<band height = "9" splitType = "Stretch"/>
</summary>
</jasperReport>
当我们使用数据源时，我们需要编写相应的POJO文件SubReportBean.java，如下所示。将其保存到目录 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint -
package com.tutorialspoint;
public class SubReportBean {
private String city;
private String street;
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
}
在这里，我们声明了两个字段“city”和“street”，并定义了各自的 getter 和 setter 方法。
现在，让我们更新现有的DataBean文件。我们将添加一个新字段subReportBeanList，它是一个 java.util.List。该字段将保存 SubReportBean 对象的列表。DataBean 文件的内容如下。将其保存到目录 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint。
package com.tutorialspoint;
import java.util.List;
public class DataBean {
private String name;
private String country;
private List<SubReportBean> subReportBeanList;
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;
}
public List<SubReportBean> getSubReportBeanList() {
return subReportBeanList;
}
public void setSubReportBeanList(List<SubReportBean> subReportBeanList) {
this.subReportBeanList = subReportBeanList;
}
}
现在让我们更新文件 C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint\ DataBeanList.java。该文件的内容如下 -
package com.tutorialspoint;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class DataBeanList {
public ArrayList<DataBean> getDataBeanList() {
// Create sub report data
SubReportBean subBean1 = new SubReportBean();
subBean1.setCity("Mumbai");
subBean1.setStreet("M.G.Road");
SubReportBean subBean2 = new SubReportBean();
subBean2.setCity("New York");
subBean2.setStreet("Park Street");
SubReportBean subBean3 = new SubReportBean();
subBean3.setCity("San Fransisco");
subBean3.setStreet("King Street");
ArrayList<DataBean> dataBeanList = new ArrayList<DataBean>();
// Create master report data
dataBeanList.add(produce("Manisha", "India",
Arrays.asList(subBean1)));
dataBeanList.add(produce("Dennis Ritchie", "USA",
Arrays.asList(subBean2)));
dataBeanList.add(produce("V.Anand", "India",
Arrays.asList(subBean1)));
dataBeanList.add(produce("Shrinath", "California",
Arrays.asList(subBean3)));
return dataBeanList;
}
/*
* This method returns a DataBean object,
* with name, country and sub report
* bean data set in it.
*/
private DataBean produce(String name, String country,
List<SubReportBean> subBean) {
DataBean dataBean = new DataBean();
dataBean.setName(name);
dataBean.setCountry(country);
dataBean.setSubReportBeanList(subBean);
return dataBean;
}
}
在上面文件的 Produce() 方法中，我们设置了 SubReportBean 的列表。
现在，让我们编写一个新的主报告模板 (jasper_report_template.jrxml)。将此文件保存到目录C:\tools\jasperreports-5.0.1\test。该文件的内容如下 -
<?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 = "jasper_report_template" language = "groovy" pageWidth = "595"
pageHeight = "842" columnWidth ="555" leftMargin = "20" rightMargin = "20"
topMargin = "20" bottomMargin = "20">
<parameter name = "SUBREPORT_DIR" class = "java.lang.String" isForPrompting = "false">
<defaultValueExpression>
<![CDATA["C:\\tools\\jasperreports-5.0.1\\test\\"]]>
</defaultValueExpression>
</parameter>
<field name = "country" class = "java.lang.String"/>
<field name = "name" class = "java.lang.String"/>
<field name = "subReportBeanList" class = "java.util.List"/>
<background>
<band splitType = "Stretch"/>
</background>
<title>
<band height = "35" splitType = "Stretch">
<staticText>
<reportElement x = "0" y = "0" width = "204" height = "34"/>
<textElement>
<font size = "26" isBold = "true"/>
</textElement>
<text><![CDATA[Contact Report]]></text>
</staticText>
</band>
</title>
<pageHeader>
<band height = "17" splitType = "Stretch"/>
</pageHeader>
<columnHeader>
<band height = "21" splitType = "Stretch"/>
</columnHeader>
<detail>
<band height = "112" splitType = "Stretch">
<staticText>
<reportElement x = "0" y = "0" width = "100" height = "20"/>
<textElement>
<font size = "12" isBold = "true"/>
</textElement>
<text><![CDATA[Name:]]></text>
</staticText>
<staticText>
<reportElement x = "0" y = "20" width = "100" height = "20"/>
<textElement>
<font size = "12" isBold = "true"/>
</textElement>
<text><![CDATA[Country:]]></text>
</staticText>
<textField>
<reportElement x = "104" y = "0" width = "277" height = "20"/>
<textElement>
<font size = "12"/>
</textElement>
<textFieldExpression class = "java.lang.String">
<![CDATA[$F{name}]]>
</textFieldExpression>
</textField>
<textField>
<reportElement x = "104" y = "20" width = "277" height = "20"/>
<textElement>
<font size = "12"/>
</textElement>
<textFieldExpression class = "java.lang.String">
<![CDATA[$F{country}]]>
</textFieldExpression>
</textField>
<subreport>
<reportElement positionType = "Float" x = "335" y = "25" width = "175"
height = "20" isRemoveLineWhenBlank = "true" backcolor = "#99ccff"/>
<dataSourceExpression>
new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource
($F{subReportBeanList})
</dataSourceExpression>
<subreportExpression class = "java.lang.String">
<![CDATA[$P{SUBREPORT_DIR} + "address_report_template.jasper"]]>
</subreportExpression>
</subreport>
<line>
<reportElement x = "0" y = "50" width = "550" height = "1"/>
</line>
</band>
</detail>
<columnFooter>
<band height = "19" splitType = "Stretch"/>
</columnFooter>
<pageFooter>
<band height = "18" splitType = "Stretch"/>
</pageFooter>
<summary>
<band height = "14" splitType = "Stretch"/>
</summary>
</jasperReport>
在上面的模板中，我们定义了一个新参数“SUBREPORT_DIR”，它定义了子报表的路径。我们定义了一个java.util.List类型的字段subReportBeanList ，它对应于文件DataBean中的属性。元素 <subreport> 具有子元素 <dataSourceExpression>。我们已将列表subReportBeanList放入JRBeanCollectionDataSource 的实例中。在子元素 <subreportExpression/> 中，我们指定了子报表名称 (AddressReport.jasper)。
现在，让我们编写一个新类CreateReport来编译和执行我们的报告模板。文件C:\tools\jasperreports-5.0.1\test\src\com\tutorialspoint\CreateReport.java的内容如下 -
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.JasperCompileManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
public class CreateReport {
public static void main(String[] args) {
String masterReportFileName = "C://tools/jasperreports-5.0.1/test"
+ "/jasper_report_template.jrxml";
String subReportFileName = "C://tools/jasperreports-5.0.1/test"
+ "/AddressReport.jrxml";
String destFileName = "C://tools/jasperreports-5.0.1/test"
+ "/jasper_report_template.JRprint";
DataBeanList DataBeanList = new DataBeanList();
ArrayList<DataBean> dataList = DataBeanList.getDataBeanList();
JRBeanCollectionDataSource beanColDataSource = new
JRBeanCollectionDataSource(dataList);
try {
/* Compile the master and sub report */
JasperReport jasperMasterReport = JasperCompileManager
.compileReport(masterReportFileName);
JasperReport jasperSubReport = JasperCompileManager
.compileReport(subReportFileName);
Map<String, Object> parameters = new HashMap<String, Object>();
parameters.put("subreportParameter", jasperSubReport);
JasperFillManager.fillReportToFile(jasperMasterReport,
destFileName, parameters, beanColDataSource);
} catch (JRException e) {
e.printStackTrace();
}
System.out.println("Done filling!!! ...");
}
}
在这里，我们看到我们正在编译主报告模板和子报告模板，并传递主报告 (.jasper) 文件以进行报告填充。
报告生成
现在，我们的所有文件都已准备就绪，让我们使用常规 ANT 构建过程来编译并执行它们。文件 build.xml（保存在目录 C:\tools\jasperreports-5.0.1\test 下）的内容如下所示。
导入文件 - baseBuild.xml 取自“环境设置”一章，并且应放置在与 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，我们打开命令行窗口并进入build.xml所在的目录。最后，执行命令ant -Dmain-class=com.tutorialspoint.CreateReport（viewFullReport 是默认目标），如下所示 -
Buildfile: C:\tools\jasperreports-5.0.1\test\build.xml
clean-sample:
[delete] Deleting directory C:\tools\jasperreports-5.0.1\test\classes
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 to
[javac] Compiling 7 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.CreateReport
[java] Compiling Report Design ...
[java] log4j:WARN No appenders could be found for logger
(net.sf.jasperreports.engine.xml.JRXmlDigesterFactory).
[java] log4j:WARN Please initialize the log4j system properly.
[java] Done filling!!! ...
viewFillReport:
[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: 72 minutes 13 seconds
作为上述编译的结果，JasperViewer 窗口将打开，如下面给出的屏幕所示 -
在这里，我们可以看到显示了名称、国家/地区和地址属性。