Trying to get Jaspersoft Studio to Read Excel Numeric Values - jasper-reports

Question

I am using Jaspersoft Studio to create a JasperReports's report using an Excel file as data source (I have a couple of columns in excel with numeric values to which i have assigned the class java.lang.Number in fields). But when previewing the report, I get the following the error
"net.sf.jasperreports.engine.JRException: unable to get value for field 'Hours' of class java.lang.Number"
Any inputs please?
Here is my jrxml file
<?xml version="1.0" encoding="UTF-8"?>
<!-- Created with Jaspersoft Studio version 5.6.1.final using JasperReports Library version 5.6.1 -->
<!-- 2014-09-25T18:35:44 -->
<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="Leaf_Grey" pageWidth="595" pageHeight="842" columnWidth="535" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="896e484a-2240-4304-afcc-7290c150d8b7">
<property name="ireport.zoom" value="1.0"/>
<property name="ireport.x" value="0"/>
<property name="ireport.y" value="0"/>
<property name="com.jaspersoft.studio.data.defaultdataadapter" value="New Data Adapter (4)"/>
<style name="Title" fontName="Arial" fontSize="26" isBold="true" pdfFontName="Helvetica-Bold"/>
<style name="SubTitle" forecolor="#666666" fontName="Arial" fontSize="18"/>
<style name="Column header" forecolor="#666666" fontName="Arial" fontSize="12" isBold="true"/>
<style name="Detail" fontName="Arial" fontSize="12"/>
<queryString>
<![CDATA[]]>
</queryString>
<field name="Task" class="java.lang.String"/>
<field name="Site Name" class="java.lang.String"/>
<field name="Hours" class="java.lang.Number"/>
<field name="Minutes" class="java.lang.Number"/>
<field name="Status" class="java.lang.String"/>
<field name="Comments" class="java.lang.String"/>
<field name="Employee Name" class="java.lang.String"/>
<background>
<band splitType="Stretch"/>
</background>
<title>
<band height="70" splitType="Stretch">
<image>
<reportElement x="275" y="0" width="300" height="64" uuid="8636fef6-bee7-4ac4-9942-653e5c68326b"/>
<imageExpression><![CDATA["leaf_banner_gray.png"]]></imageExpression>
</image>
<staticText>
<reportElement style="Title" x="0" y="13" width="263" height="33" uuid="4370ee46-32ee-4993-8fc6-fff1a5cbbb10"/>
<textElement verticalAlignment="Middle"/>
<text><![CDATA[Leaf Gray Title]]></text>
</staticText>
<staticText>
<reportElement style="SubTitle" x="117" y="46" width="157" height="22" uuid="e0a627c7-e8b9-4efb-8e25-85fea9d9be9c"/>
<text><![CDATA[Leaf Gray SubTitle]]></text>
</staticText>
</band>
</title>
<pageHeader>
<band splitType="Stretch"/>
</pageHeader>
<columnHeader>
<band height="36" splitType="Stretch">
<line>
<reportElement positionType="FixRelativeToBottom" x="0" y="35" width="555" height="1" uuid="8545dbd1-d876-4d96-8abf-d6b221e00a45"/>
<graphicElement>
<pen lineWidth="0.5" lineColor="#999999"/>
</graphicElement>
</line>
<staticText>
<reportElement style="Column header" x="0" y="19" width="79" height="15" uuid="cac2a980-c74e-44b0-b596-05d495272ccb"/>
<text><![CDATA[Task]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="79" y="19" width="79" height="15" uuid="d55bebe9-d167-4528-a78c-a5a41af89efc"/>
<text><![CDATA[Site Name]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="158" y="19" width="79" height="15" uuid="667ce640-c671-4337-8f0c-d23b3f4b273c"/>
<text><![CDATA[Hours]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="237" y="19" width="79" height="15" uuid="df472e1f-39fb-4b34-b0b3-0867407df860"/>
<text><![CDATA[Minutes]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="316" y="19" width="79" height="15" uuid="05e27ddd-a03c-4ad6-8596-5cfc00655de7"/>
<text><![CDATA[Status]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="395" y="19" width="79" height="15" uuid="cefa7fbe-75bd-4923-82a6-da21a13d4f58"/>
<text><![CDATA[Comments]]></text>
</staticText>
<staticText>
<reportElement style="Column header" x="474" y="19" width="79" height="15" uuid="090b77e6-6a38-43b4-8501-6e1c3e246764"/>
<text><![CDATA[Employee Name]]></text>
</staticText>
</band>
</columnHeader>
<detail>
<band height="16" splitType="Stretch">
<line>
<reportElement positionType="FixRelativeToBottom" x="0" y="15" width="555" height="1" uuid="9b18ea63-f82d-4ef1-872e-8fde09656872"/>
<graphicElement>
<pen lineWidth="0.5" lineColor="#999999"/>
</graphicElement>
</line>
<textField>
<reportElement style="Detail" x="0" y="0" width="79" height="15" uuid="1f24eaab-1923-419e-9262-79b6c2b80499"/>
<textFieldExpression><![CDATA[$F{Task}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="79" y="0" width="79" height="15" uuid="f9b21e3a-3150-4744-a413-10cf734a2c3d"/>
<textFieldExpression><![CDATA[$F{Site Name}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="158" y="0" width="79" height="15" uuid="867d0368-9589-4c6b-8502-f71224a11a4c"/>
<textFieldExpression><![CDATA[$F{Hours}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="237" y="0" width="79" height="15" uuid="17715223-dbc6-462a-b80c-aeb54aa58932"/>
<textFieldExpression><![CDATA[$F{Minutes}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="316" y="0" width="79" height="15" uuid="3a3115d3-420d-4411-88cc-30b41f67443e"/>
<textFieldExpression><![CDATA[$F{Status}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="395" y="0" width="79" height="15" uuid="97194b34-07e1-49b4-aba0-af1efe7b9bf4"/>
<textFieldExpression><![CDATA[$F{Comments}]]></textFieldExpression>
</textField>
<textField>
<reportElement style="Detail" x="474" y="0" width="79" height="15" uuid="ba21b35b-74a9-45ee-862f-8752756350dd"/>
<textFieldExpression><![CDATA[$F{Employee Name}]]></textFieldExpression>
</textField>
</band>
</detail>
<columnFooter>
<band height="45" splitType="Stretch">
<line>
<reportElement positionType="FixRelativeToBottom" x="0" y="3" width="555" height="1" uuid="7d65af8c-8abe-40ae-9953-98342530289f"/>
<graphicElement>
<pen lineWidth="0.5" lineColor="#999999"/>
</graphicElement>
</line>
</band>
</columnFooter>
<pageFooter>
<band height="20" splitType="Stretch">
<textField>
<reportElement style="Column header" x="433" y="0" width="80" height="20" uuid="afe06d42-bf57-40c1-9cbb-6e8a04a641e6"/>
<textElement textAlignment="Right">
<font size="10" isBold="false"/>
</textElement>
<textFieldExpression><![CDATA["Page "+$V{PAGE_NUMBER}+" of"]]></textFieldExpression>
</textField>
<textField evaluationTime="Report">
<reportElement style="Column header" x="513" y="0" width="40" height="20" uuid="ee38e653-d5c9-4269-93a3-b1dcd2685d2c"/>
<textElement>
<font size="10" isBold="false"/>
</textElement>
<textFieldExpression><![CDATA[" " + $V{PAGE_NUMBER}]]></textFieldExpression>
</textField>
<textField pattern="EEEEE dd MMMMM yyyy">
<reportElement style="Column header" x="0" y="0" width="197" height="20" uuid="af6b71ba-3c04-4b3c-9b70-e18e46b27ff4"/>
<textElement>
<font size="10" isBold="false"/>
</textElement>
<textFieldExpression><![CDATA[new java.util.Date()]]></textFieldExpression>
</textField>
</band>
</pageFooter>
<summary>
<band splitType="Stretch"/>
</summary>
</jasperReport>
And a sample excel file as follows:
Task Site Name Hours Minutes Status Comments Employee Name
Task A abc.com 3 45 Ongoing Easy Jim
Task B abc.com 1 20 Done Easy John
Task C abc.com 3 30 Ongoing Easy Jim
Task A abc.com 1 20 Done Easy John
Task D abc.com 3 45 Ongoing Easy Mary
Task A abc.com 1 20 Done Easy Stacy
Task E abc.com 3 30 Ongoing Easy Stacy
Task A abc.com 1 20 Done Easy Stacy

Answer 1

1) If the requirement is to change the Class to Number from String then, you need to click the checkbox "Use custom number pattern" and select a number pattern.
2) If there is no specific requirement, then its easy to select java.lang.Integer as the class for numbers. This will make the report work just fine.