Subreport Data Source Expression for XML document - xpath

Question

I'm trying to get a subreport working for a report using an XML document as a data source.
When I'm sorting main report data, subreport won't have to requery the XML document. Its expecting a JRSortableDataSource, not a JRXmlDataSource.
What am I doing wrong?
I used following datasource expression:
$P{REPORT_DATA_SOURCE}).subDataSource("/person/phone")
The stack trace:
Error filling print... Error evaluating expression : Source text : $P{REPORT_DATA_SOURCE}.subDataSource("/person/phone")
net.sf.jasperreports.engine.fill.JRExpressionEvalException: Error evaluating expression :
Source text : $P{REPORT_DATA_SOURCE}.subDataSource("/person/phone")
at net.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:203)
at net.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:591)
at net.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:559)
at net.sf.jasperreports.engine.fill.JRFillElement.evaluateExpression(JRFillElement.java:966)
at net.sf.jasperreports.engine.fill.JRFillSubreport.evaluateSubreport(JRFillSubreport.java:384)
at net.sf.jasperreports.engine.fill.JRFillSubreport.evaluate(JRFillSubreport.java:286)
at net.sf.jasperreports.engine.fill.JRFillElementContainer.evaluate(JRFillElementContainer.java:259)
at net.sf.jasperreports.engine.fill.JRFillBand.evaluate(JRFillBand.java:459)
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillColumnBand(JRVerticalFiller.java:2044)
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillDetail(JRVerticalFiller.java:778)
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReportStart(JRVerticalFiller.java:288)
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:151)
at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:909)
at net.sf.jasperreports.engine.fill.JRFiller.fill(JRFiller.java:126)
at net.sf.jasperreports.engine.JasperFillManager.fill(JasperFillManager.java:464)
at net.sf.jasperreports.engine.JasperFillManager.fill(JasperFillManager.java:300)
at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:757)
at com.jaspersoft.ireport.designer.compiler.IReportCompiler.run(IReportCompiler.java:1003)
at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)
at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997) Caused by: groovy.lang.MissingMethodException:
No signature of method: net.sf.jasperreports.engine.fill.SortedDataSource.subDataSource()
is applicable for argument types: (java.lang.String) values: [/person/phone]
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:54)
at org.codehaus.groovy.runtime.callsite.PojoMetaClassSite.call(PojoMetaClassSite.java:46)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:40)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:124)
at TestParam_1362739351228_895383.evaluate(calculator_TestParam_1362739351228_895383:223)
at net.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:190)

Answer 1

Your datasource expression $P{REPORT_DATA_SOURCE}).subDataSource("/B/C")
Has a syntax error
You missed unmatched character at first (
Then
If its expecting a JRSortableDataSource
Use this expression
((net.sf.jasperreports.engine.data.JRSortableDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("DefineThat")
If its expecting a JRXmlDataSource
Use this expression
((net.sf.jasperreports.engine.data.JRXmlDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("DefineThat")

Answer 2

$P{REPORT_DATA_SOURCE}).subDataSource("Xpath")
when somebody uses the above expression to connect to create sub report in Jasper using XML Datasource we need to set the Report Language as groovy instead of Java .I think subdatasource is not a method defined in Java but in groovy .I'm trying to find a method which is equivalent to above in Java

Answer 3

Had the same issue, found this solution at the jaspersoft-community:
Capturing the original data source in a parameter:
<parameter name="MyDataSource" class="net.sf.jasperreports.engine.JRDataSource" isForPrompting="false">
<defaultValueExpression><![CDATA[$P{REPORT_DATA_SOURCE}]]></defaultValueExpression>
</parameter>
same in iReport-GUI:
create new paramater at the main report
Name: "MyDataSource"
Parameter Class: "net.sf.jasperreports.engine.JRDataSource"
Use as a prompt: No
Default value Expression: "$P{REPORT_DATA_SOURCE}"
Now using the MyDataSource Parameter at the subreport-datasource:
<dataSourceExpression><![CDATA[((net.sf.jasperreports.engine.data.JRXmlDataSource)$P{MyDataSource}).dataSource("/Subreport/path")]]></dataSourceExpression>