Custom DataSource - Why exception?

[kjhuebner]

Hi,

I've been trying to get a master and subreport to work using a custom datasource having a hierarchical structure. (See attached .zip file for full details) The datasource is composed of a list of rows (list of Maps with fieldname,value pairs) and associated with each row is a "sub" datasource (containing list of Maps with fieldname,value pairs).

 

However, when I run report, it fails at filling the subreport due to failing at retrieving the "sub" datasource. My master template contains this snippet:

 

<subreport>

...

<parametersMapExpression><![CDATA[$P{REPORT_PARAMETERS_MAP}]]></parametersMapExpression>

 

<dataSourceExpression><![CDATA[$P{REPORT_DATA_SOURCE}.getSubDataSourceFromRow("Tasks")]]></dataSourceExpression>

...

</subreport>

 

I'm not sure how to interpret the exception--as its failing deep in the Jasper engine.

I tried explicitly casting the datasource with the classname of my custom data source, but it still fails.

 

If anyone can explain what is going on, I'd appreciate it.

Thanks!

Ken

--------------

TRACE....

 

ErrorÂfillingÂprint...

ENTEREDÂTestDataSourceFactory.getTheDatasource() ENTEREDÂTestDataSource()ÂCONSTRUCTOR ENTEREDÂaddRowÂindex=0 ENTEREDÂTestDataSource(List)ÂCONSTRUCTOR ENTEREDÂTestDataSource.putSubDataSourceFromRow()Âkey=Tasks ENTEREDÂaddRowÂindex=1 ENTEREDÂTestDataSource(List)ÂCONSTRUCTOR ENTEREDÂTestDataSource.putSubDataSourceFromRow()Âkey=Tasks java.lang.ClassCastException:Âcom.catalystwms.cct.web.beans.reports.TestDataSource ÂÂÂÂatÂTestDataSource_1154462782283_984118.evaluate(TestDataSource_1154462782283_984118:124) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:172) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:556) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:524) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setFillParameterValues(JRFillDataset.java:601) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setParameterValues(JRFillDataset.java:563) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.setParameters(JRBaseFiller.java:878) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:689) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:666) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:89) ÂÂÂÂatÂnet.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:601) ÂÂÂÂatÂit.businesslogic.ireport.IReportCompiler.run(IReportCompiler.java:713) ÂÂÂÂatÂjava.lang.Thread.run(UnknownÂSource) NESTEDÂBYÂ: java.lang.ClassCastException:Âcom.catalystwms.cct.web.beans.reports.TestDataSource ÂÂÂÂatÂTestDataSource_1154462782283_984118.evaluate(TestDataSource_1154462782283_984118:124) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:172) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:556) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:524) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setFillParameterValues(JRFillDataset.java:601) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setParameterValues(JRFillDataset.java:563) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.setParameters(JRBaseFiller.java:878) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:689) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:666) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:89) ÂÂÂÂatÂnet.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:601) ÂÂÂÂatÂit.businesslogic.ireport.IReportCompiler.run(IReportCompiler.java:713) ÂÂÂÂatÂjava.lang.Thread.run(UnknownÂSource) NESTEDÂBYÂ: net.sf.jasperreports.engine.fill.JRExpressionEvalException:ÂErrorÂevaluatingÂexpressionÂ:Â ÂÂÂÂSourceÂtextÂ:Â$P{REPORT_DATA_SOURCE} ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:183) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:556) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:524) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setFillParameterValues(JRFillDataset.java:601) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFillDataset.setParameterValues(JRFillDataset.java:563) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.setParameters(JRBaseFiller.java:878) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:689) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:666) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:89) ÂÂÂÂatÂnet.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:601) ÂÂÂÂatÂit.businesslogic.ireport.IReportCompiler.run(IReportCompiler.java:713) ÂÂÂÂatÂjava.lang.Thread.run(UnknownÂSource) CausedÂby:Âjava.lang.ClassCastException:Âcom.catalystwms.cct.web.beans.reports.TestDataSource ÂÂÂÂatÂTestDataSource_1154462782283_984118.evaluate(TestDataSource_1154462782283_984118:124) ÂÂÂÂatÂnet.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:172) ÂÂÂÂ...Â11Âmore

PrintÂnotÂfilled.ÂTryÂtoÂuseÂanÂEmptyDataSource...!

 

 

 

 

 

[file name=TestDataSource.zip size=27835]http://www.jasperforge.org/components/com_joomlaboard/uploaded/files/TestDataSource.zip[/file] [file name=TestDataSource.zip size=27835]http://www.jasperforge.org/components/com_joomlaboard/uploaded/files/TestDataSource.zip[/file]

[Giulio Toffoli]

This kind of errors can happen with dynamic classpaths.

Put your classes in ireport/classes or inside a jar in iReport/lib

 

Giulio

[kjhuebner]

It's still failing on getting subreport's datasource (class cast exception).

 

Regarding your classpath theory, I'm already using a static classpath defined within IReport under Options | Classpath. Also, IReport finds my classes during Connection setup as it gives me an OK message.

 

1. Are there any other classpaths I have to define in IReport?

 

2. Can I assume that my custom TestDataSource IS the value contained in REPORT_DATA_SOURCE when I run the report? My reasoning is that since I have setup up a factory to return my TestDataSource using IReport's Connection setup dialog and tested OK. Whereby, when I run report within IReport shouldn't this work?

 

<subreport isUsingCache="false">

...

<dataSourceExpression><![CDATA[((com.catalystwms.cct.web.beans.reports.TestDataSource)$P{REPORT_DATA_SOURCE}).getSubDataSourceFromRow("Tasks")]]></dataSourceExpression>

...

</subreport>

 

3. Or will this not work within the IReport tool and I have to run this outside the tool? But then what good is the tool if I cannot observe the simplest of test data being processed by Jasper?

 

Ken