I'm unable to pass data from main report to subreport with XML as data. The approach I'm taking is have a MainReport with two sub reports in it SubReport1 and SubReport2. XPath for SubReport1 is /main-report/sub-report1/items/item similarly XPath for SubReport2 is /main-report/sub-report2/items/item. Below is sample xml
<main-report>
<sub-report1>
<header></header>
<items>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
</items>
<footer></footer>
</sub-report1>
<sub-report2>
<header></header>
<items>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
<item></item>
</items>
<footer></footer>
</sub-report2>
</main-report>
2 Answers:
Don't use absolute path starting from /main-report
Use relative path
https://community.jaspersoft.com/questions/524978/empty-subreport-xml-da...
Finally, was able to solve problem. With above XML as Datasource.
Main Report
Step 1: Have xPath as /main-report
<queryString language="xPath">
<![CDATA[/main-report]]>
</queryString>
Step 2: Data Source Expression for sub report 1
((net.sf.jasperreports.engine.data.JRXmlDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("//main-report/sub-report1/line-items/line-item"
Step 3: Data Source Expression for Sub Report 2
((net.sf.jasperreports.engine.data.JRXmlDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("//main-report/sub-report2/line-items/line-item")
Sub Report 1
<queryString language="xPath">
<![CDATA[/main-report/sub-report1/line-items/line-item]]>
</queryString>
Sub Report 2
<queryString language="xPath">
<![CDATA[/main-report/sub-report2/line-items/line-item]]>
</queryString>
