Need to fill data sheet in excel via xsl for pivot report

Using XSLT I am able to create a XML Spread Sheet with xml raw data and the same can be viewed by MircoSoft excel or open office calc.

Here I need to do pivot report using a xml spread sheet data. Let us assume a work book contains two sheets

Sheet1 is "Data" Sheet,
Sheet2 is "PivotReport" sheet

Pivot Report sheet is predefined and Data sheet is dynamic. Using java I need to open data sheet fill data dynamically. I tried apache POI but its throwing Invocation target exception when accessing sheet.

Is there any other way to fill data sheet ? Thanks.

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