Understanding Jrxml with a custom datasource - jasper-reports

Question

I am creating a Jasper report using a custom datasource.
I am using iReport to create the report.
Although I can see report working following various articles on web, I fail to understand how the generated Jrxml knows that it is supposed to fetch data from a custom JRDatasource ?
I can't see Jrxml pointing to my custom datasource class anywhere ???
Can someone provide more information ?
Here is the generated Jrxml
<?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="test" pageWidth="595" pageHeight="842" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="a19f56bb-4764-4dad-8177-9a410a0cb69d">
<property name="com.jaspersoft.studio.data.defaultdataadapter" value="New Data Adapter "/>
<queryString>
<![CDATA[]]>
</queryString>
<field name="productCode" class="java.lang.String"/>
<field name="stockLevelStatus" class="java.lang.String">
<fieldDescription><![CDATA[stockLevelStatus]]></fieldDescription>
</field>
<background>
<band splitType="Stretch"/>
</background>
<pageHeader>
<band height="35" splitType="Stretch"/>
</pageHeader>
<detail>
<band height="125" splitType="Stretch">
<textField>
<reportElement x="10" y="60" width="100" height="30" uuid="53ec360c-996a-48eb-9777-efbb9d5fa3d7"/>
<textFieldExpression><![CDATA[$F{productCode}]]></textFieldExpression>
</textField>
<staticText>
<reportElement x="10" y="0" width="100" height="30" uuid="dc8fcc8f-6294-4d5b-97de-4b68d2e6bb8b"/>
<text><![CDATA[productCode]]></text>
</staticText>
<textField>
<reportElement x="140" y="60" width="100" height="30" uuid="5219cffe-1786-4bd8-a8af-83eebda483cf"/>
<textFieldExpression><![CDATA[$F{stockLevelStatus}]]></textFieldExpression>
</textField>
<staticText>
<reportElement x="140" y="0" width="100" height="30" uuid="27edec96-50c6-4de0-830a-9593a0da7c17"/>
<text><![CDATA[stockLevelStatus]]></text>
</staticText>
</band>
</detail>
</jasperReport>
Can someone share Jrxml with custom datasource ?

Answer 1

Finally after a lot of R&D, I am able to solve the problem.
Here is the ".jrxml" file which allows you to plot a table in a Jasper report where table's data comes from a custom datasource.
You can find quite a few articles on web explaining how to write a custom datasource but none of them provides an example of how to use a custom datasource in a jrxml file.
<?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="custom" language="groovy" pageWidth="595" pageHeight="420" whenNoDataType="BlankPage" columnWidth="595" leftMargin="0" rightMargin="0" topMargin="0" bottomMargin="0" scriptletClass="de.hybris.platform.cockpit.reports.scriptlets.DateTimeScriptlet" resourceBundle="localization/jasperreports">
<property name="ireport.zoom" value="1.0"/>
<property name="ireport.x" value="0"/>
<property name="ireport.y" value="0"/>
<subDataset name="custome_datasource">
<queryString>
<![CDATA[select 1 from DUAL]]>
</queryString>
<field name="productCode" class="java.lang.String"/>
<field name="stockLevelStatus" class="java.lang.String">
<fieldDescription><![CDATA[stockLevelStatus]]></fieldDescription>
</field>
</subDataset>
<queryString>
<![CDATA[select 1 from DUAL]]>
</queryString>
<title>
<band height="80" splitType="Stretch">
<staticText>
<reportElement x="10" y="0" width="500" height="30"/>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font fontName="Arial" size="16" isBold="true"/>
</textElement>
<text><![CDATA[Stock Level Status Report]]></text>
</staticText>
</band>
</title>
<detail>
<band height="340" splitType="Stretch">
<componentElement>
<reportElement key="table" x="0" y="0" width="555" height="238"/>
<jr:table xmlns:jr="http://jasperreports.sourceforge.net/jasperreports/components" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports/components http://jasperreports.sourceforge.net/xsd/components.xsd">
<datasetRun subDataset="custome_datasource">
<dataSourceExpression><![CDATA[new my.dataproviders.StockLevelDataProvider()]]></dataSourceExpression>
</datasetRun>
<jr:column width="130">
<jr:columnHeader height="30" rowSpan="1">
<staticText>
<reportElement x="0" y="0" width="92" height="25" backcolor="#99CCFF"/>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font fontName="Arial" size="9" isBold="true"/>
</textElement>
<text><![CDATA[ProductCode]]></text>
</staticText>
</jr:columnHeader>
<jr:detailCell height="30" rowSpan="1">
<textField>
<reportElement x="0" y="10" width="90" height="20"/>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font fontName="Arial" size="9" isBold="false"/>
</textElement>
<textFieldExpression class="java.lang.String"><![CDATA[$F{productCode}]]></textFieldExpression>
</textField>
</jr:detailCell>
</jr:column>
<jr:column width="130">
<jr:columnHeader height="30" rowSpan="1">
<staticText>
<reportElement x="0" y="0" width="92" height="25" backcolor="#99CCFF"/>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font fontName="Arial" size="9" isBold="true"/>
</textElement>
<text><![CDATA[StockLevel]]></text>
</staticText>
</jr:columnHeader>
<jr:detailCell height="30" rowSpan="1">
<textField>
<reportElement x="0" y="10" width="90" height="20"/>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font fontName="Arial" size="9" isBold="false"/>
</textElement>
<textFieldExpression class="java.lang.String"><![CDATA[$F{stockLevelStatus}]]></textFieldExpression>
</textField>
</jr:detailCell>
</jr:column>
</jr:table>
</componentElement>
</band>
</detail>