填写报告的主要输入是 : 报告模板,参数和数据源.本章将介绍参数,在下一章中我们将讨论数据源.
参数是对象引用,它们在报表填充操作期间传递给报表引擎.无法通过数据源传递的数据可以使用参数传递.作者姓名,报告标题等数据可以通过参数传递. JasperReports模板或JRXML模板可以包含零个或多个参数元素.
参数声明如下 :
< parameter name ="exampleParameter"class ="java.lang.String"/>
<参数>的名称属性元素是强制性的.它按名称引用报表表达式中的参数.参数名称应该是单个单词.它不应包含任何特殊字符,如点或逗号.
类属性也是必需的它指定参数值的类名.它的默认值是 java.lang.String .这可以更改为运行时可用的任何类.无论报表参数的类型如何,引擎都会在使用$ P {}标记的报表表达式中进行转换,因此不需要手动转换.
报告参数值始终打包在java.util.Map对象中,该对象的参数名称为其键.报告参数可以在报告的查询字符串中使用,以便进一步自定义从数据库中检索的数据集.它们就像查询中的动态过滤器一样,为报告提供数据.
以下是预定义的报告参数,准备在表达式中使用 :
S.NO | 参数名称和描述 |
---|---|
1 | REPORT_PARAMETERS_MAP 包含一张包含所有用户定义和内置参数的地图. |
2 | REPORT_CONNECTION 这指向用户提供的类java.sql.Connection,用于JDBC数据源. |
3 | REPORT_DATA_SOURCE 这是一个用户提供的JRDataSource实例,代表其中一个内置数据源类型或用户定义的数据源类型. |
4 | REPORT_MAX_COUNT 这是一个 java.lang.Integer 值,允许用户限制来自数据源的记录. |
5 | REPORT_SCRIPTLET 这指向 net.sf.jasperreports.engine.JRAbstractScriptlet 并包含用户提供的报告scriptlet的实例. |
6 | REPORT_LOCALE 这是一个 java.util.Locale 实例,包含所需的资源包区域设置. |
7 | REPORT_RESOURCE_BUNDLE 这指向 java.util.ResourceBundle 对象并包含本地化消息. |
8 | REPORT_TIME_ZONE 这是一个 java.util.TimeZone 实例,用于日期格式化. |
9 | REPORT_VIRTUALIZER 这是一个实例 net.sf.jasperreports.engine.JRVirtualizer 对象的e,用于页面虚拟化(优化内存消耗). |
10 | REPORT_CLASS_LOADER 这是 java.lang.ClassLoader 在报告填充过程中用于加载图像,字体和子报告模板等资源的实例 |
11 | IS_IGNORE_PAGINATION 如果设置为 java.lang.Boolean.TRUE 报告将在一个长页面上生成,并且不会发生分页. |
让我们将 ReportTitle 和 Author 传递给报告(由JasperReportFill生成. JAVA).修订后的文件 C:\tools\jasperreports-5.0.1\test\src\com\it1352\ JapersReportFill.java 如下 :
package com.it1352; 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(); /** * Passing ReportTitle and Author as parameters */ parameters.put("ReportTitle", "List of Contacts"); parameters.put("Author", "Prepared By Manisha"); try { JasperFillManager.fillReportToFile( sourceFileName, parameters, beanColDataSource); } catch (JRException e) { e.printStackTrace(); } } }
POJO文件的内容 C:\tools\jasperreports -5.0.1\test\src\com\it1352\ DataBean.java 如下 :
package com.it1352; 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; } }
文件的内容 C:\tools\jasperreports-5.0.1 \ test \src\com\it1352\ DataBeanList.java 如下所示 :
package com. it1352; 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; } }
让我们添加参数< ReportTitle >和< 作者>到我们现有的报告模板(章节报告设计).报告标题和作者将显示在报告的开头.修订后的报告模板(jasper_report_template.jrxml)如下所示.将其保存到C:\tools\jasperreports-5.0.1 \ test目录 :
<?xml version = "1.0"?> <!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" pageWidth = "595" pageHeight = "842" columnWidth = "515" leftMargin = "40" rightMargin = "40" topMargin = "50" bottomMargin = "50"> <parameter name = "ReportTitle" class = "java.lang.String"/> <parameter name = "Author" class = "java.lang.String"/> <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> <title> <band height = "70"> <line> <reportElement x = "0" y = "0" width = "515" height = "1"/> </line> <textField isBlankWhenNull = "true" bookmarkLevel = "1"> <reportElement x = "0" y = "10" width = "515" height = "30"/> <textElement textAlignment = "Center"> <font size = "22"/> </textElement> <textFieldExpression class = "java.lang.String"> <![CDATA[$P{ReportTitle}]]> </textFieldExpression> <anchorNameExpression> <![CDATA["Title"]]> </anchorNameExpression> </textField> <textField isBlankWhenNull = "true"> <reportElement x = "0" y = "40" width = "515" height = "20"/> <textElement textAlignment = "Center"> <font size = "10"/> </textElement> <textFieldExpression class = "java.lang.String"> <![CDATA[$P{Author}]]> </textFieldExpression> </textField> </band> </title> <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>
我们将使用常规ANT构建过程编译并执行上述文件.文件build.xml的内容(保存在目录C:\tools \jasperreports-5.0.1 \ test下面)如下所示.
导入文件 - baseBuild.xml从环境设置一章中挑选,并且应该与build.xml放在同一目录中.
<?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build.xml所在的目录.最后,执行命令 ant -Dmain-class = com.it1352.JasperReportFill (viewFullReport是默认目标),如下所示 :
C:\tools\jasperreports-5.0.1\test>ant -Dmain-class=com.IT屋.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 to build.sysclasspath=last; set to false for repeatable builds [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.IT屋.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. 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: 18 seconds
由于上面的编译,JasperViewer窗口打开为显示在以下屏幕 :
此处,我们看到,ReportTitle"联系人列表"和作者"由Manisha准备"显示在报告的开头.