JasperReports如何使用HTML标记显示CLOB字段

Question

我想在 Detail 频段中显示值。来自 Oracle DB 的数据类型为 clob ，其值包含 HTML 标记

我收到此错误消息：

Error filling print... Error evaluating expression :     
Source text : $F{DISCHARGE_TEXT}.getSubString( 1l, ( new Long( $F{DISCHARGE_TEXT}.length() ) ).intValue())

net.sf.jasperreports.engine.fill.JRExpressionEvalException: Error evaluating expression :     
 Source text : $F{DISCHARGE_TEXT}.getSubString( 1l, ( new Long( $F{DISCHARGE_TEXT}.length() ) ).intValue())      
at net.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:195)      
at net.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:589)      
at net.sf.jasperreports.engine.fill.JRCalculator.evaluate(JRCalculator.java:557)      
at net.sf.jasperreports.engine.fill.JRFillElement.evaluateExpression(JRFillElement.java:929)      
at net.sf.jasperreports.engine.fill.JRFillTextField.evaluateText(JRFillTextField.java:383)      
at net.sf.jasperreports.engine.fill.JRFillTextField.evaluate(JRFillTextField.java:368)      
at net.sf.jasperreports.engine.fill.JRFillElementContainer.evaluate(JRFillElementContainer.java:258)      
at net.sf.jasperreports.engine.fill.JRFillBand.evaluate(JRFillBand.java:499)      
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillColumnBand(JRVerticalFiller.java:2033)      
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillDetail(JRVerticalFiller.java:760)      
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReportStart(JRVerticalFiller.java:270)      
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:128)      
at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:946)      
at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:845)      
at net.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:58)      
at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:417)      
at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:247)      
at com.jaspersoft.ireport.designer.compiler.IReportCompiler.run(IReportCompiler.java:877)      
at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)      
at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997)  
Caused by: java.lang.ClassCastException: oracle.sql.CLOB cannot be cast to oracle.sql.CLOB      
at testReport_1377507739843_118503.evaluate(testReport_1377507739843_118503:199)      
at net.sf.jasperreports.engine.fill.JREvaluator.evaluate(JREvaluator.java:182)      ... 19 more  
Print not filled. Try to use an EmptyDataSource...

我应用了类似的东西但未能运行报告

$F{DISCHARGE_TEXT}.getSubString( 1l, ( new Long( $F{DISCHARGE_TEXT}.length() ) ).intValue())

jrxml

<?xml version="1.0" encoding="UTF-8"?>
<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="report1" language="groovy" pageWidth="595" pageHeight="842" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="c9787a67-b067-4421-a7b5-e13d0e6785d8">
    <property name="ireport.zoom" value="1.0"/>
    <property name="ireport.x" value="0"/>
    <property name="ireport.y" value="0"/>
    <queryString language="SQL">
        <![CDATA[select DISCHARGE_TEXT
 from ip_discharge
 where admission_no='A011303011860']]>
    </queryString>
    <field name="DISCHARGE_TEXT" class="oracle.sql.CLOB"/>
    <background>
        <band splitType="Stretch"/>
    </background>
    <title>
        <band height="79" splitType="Stretch"/>
    </title>
    <pageHeader>
        <band height="35" splitType="Stretch"/>
    </pageHeader>
    <columnHeader>
        <band height="61" splitType="Stretch">
            <staticText>
                <reportElement uuid="ac99f9c5-28bf-410d-aee2-8ad5bdb95708" x="293" y="2" width="100" height="20"/>
                <textElement/>
                <text><![CDATA[DISCHARGE_TEXT]]></text>
            </staticText>
        </band>
    </columnHeader>
    <detail>
        <band height="125" splitType="Stretch">
            <textField>
                <reportElement uuid="9d6fdb47-3f70-4620-9cf8-17fcc2be4da8" x="293" y="55" width="100" height="20"/>
                <textElement/>
                <textFieldExpression><![CDATA[$F{DISCHARGE_TEXT}.getSubString( 1l, ( new Long( $F{DISCHARGE_TEXT}.length() ) ).intValue())]]></textFieldExpression>
            </textField>
        </band>
    </detail>
    <columnFooter>
        <band height="45" splitType="Stretch"/>
    </columnFooter>
    <pageFooter>
        <band height="54" splitType="Stretch"/>
    </pageFooter>
    <summary>
        <band height="42" splitType="Stretch"/>
    </summary>
</jasperReport>