I have report footer with page number and a confidential disclaimer. I need to hide confidential disclaimer in summary pages but need page number as it is.

I have added isSummaryNewPage="true" and isSummaryWithPageHeaderAndFooter="true" to the report.

Is there any flag to check whether the page is summary page or detail page inside <printWhenExpression> </printWhenExpression> or <textFieldExpression> </textFieldExpression>?

AFIK There is no built in property that tells you that you are on summary band.

However, I think this is a case where you safely can use what I call the "parameter hack" solution if summary band is on multiple page or for any another reason you don't like to use the lastPageFooter band.

The parameter hack solution

1. 
   

   Add a parameter that is a java.util.Set (you can also use List, Map or other similar classes). Instance it with an empty HashSet.

   
   
   

   <parameter name="paramHack" class="java.util.Set">
    <defaultValueExpression><![CDATA[new java.util.HashSet()]]> </defaultValueExpression>
   </parameter>
   

   
   


2. 
   

   In a textField (in your case first on summary band), add a key to it in printWhenExpression, be careful the expression can be evaluated more then one time so always make sure it returns true.

   
   
   

   <printWhenExpression><![CDATA[$PparamHack.add("summary") || true]]></printWhenExpression>
   

   
   


3. 
   

   You can now use $PparamHack.contains("summary") to know if the textField has been evaluated, hence in case to know if we have arrived to summary band and not print the "confidential disclaimer".

   
   
   

   <printWhenExpression><![CDATA[!$PparamHack.contains("summary")]]></printWhenExpression>
   

   
   

Example

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="WhenSummary" pageWidth="595" pageHeight="842" whenNoDataType="AllSectionsNoDetail" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" isSummaryNewPage="true" isSummaryWithPageHeaderAndFooter="true" uuid="bbec9a5c-d9fc-4e29-b2b0-cea6d7a50394">
 <parameter name="paramHack" class="java.util.Set">
 <defaultValueExpression><![CDATA[new java.util.HashSet()]]></defaultValueExpression>
 </parameter>
 <queryString>
 <![CDATA[]]>
 </queryString>
 <pageHeader>
 <band height="35" splitType="Stretch"/>
 </pageHeader>
 <detail>
 <band height="40">
 <staticText>
 <reportElement x="0" y="0" width="545" height="40" uuid="74f6c3de-9867-4895-b7bb-c9cdb124fbdc"/>
 <textElement textAlignment="Center" verticalAlignment="Middle">
 <font size="26"/>
 </textElement>
 <text><![CDATA[First just an empty page]]></text>
 </staticText>
 </band>
 </detail>
 <pageFooter>
 <band height="40" splitType="Stretch">
 <textField>
 <reportElement x="50" y="0" width="440" height="40" uuid="af5f6f4c-fe77-4f07-a080-035230123f50">
 <printWhenExpression><![CDATA[!$PparamHack.contains("summary")]]></printWhenExpression>
 </reportElement>
 <textElement textAlignment="Center" verticalAlignment="Middle">
 <font size="26"/>
 </textElement>
 <textFieldExpression><![CDATA["Confidential"]]></textFieldExpression>
 </textField>
 <textField>
 <reportElement x="493" y="0" width="60" height="40" uuid="78b7b8bd-4189-42ea-8120-5a09a8b5701c"/>
 <textElement textAlignment="Center" verticalAlignment="Middle">
 <font size="22"/>
 </textElement>
 <textFieldExpression><![CDATA[$VPAGE_NUMBER]]></textFieldExpression>
 </textField>
 </band>
 </pageFooter>
 <summary>
 <band height="40" splitType="Stretch">
 <staticText>
 <reportElement x="0" y="0" width="545" height="40" uuid="9ee45216-e7e1-4e5a-bbed-1f057ade1967">
 <printWhenExpression><![CDATA[$PparamHack.add("summary") || true]]></printWhenExpression>
 </reportElement>
 <textElement textAlignment="Center" verticalAlignment="Middle">
 <font size="26"/>
 </textElement>
 <text><![CDATA[Summary page]]></text>
 </staticText>
 </band>
 </summary>
</jasperReport>

Output

If you also like to use this solution for summary pageHeader (that starts before summary, but after detail band) you can for example add a "fake" group and in the group footer band (that is evaluated after detail band, but before page header on summary band) add another property to our paramHack parameter detail_end.

<group name="FakeGroup">
 <groupExpression><![CDATA["dummy"]]></groupExpression>
 <groupFooter>
 <band height="1">
 <textField>
 <reportElement x="0" y="0" width="553" height="1" uuid="373fc74e-011a-4f03-9cd4-9d5d9464ab06">
 <printWhenExpression><![CDATA[$PparamHack.add("detail_end") && false]]></printWhenExpression>
 </reportElement>
 <textFieldExpression><![CDATA["Hidden used just to know when detail band ends"]]></textFieldExpression>
 </textField>
 </band>
 </groupFooter>
</group>

Note: I have used another name, since this will be set before pageFooter on last detail band page, hence you can't use same name of flag for both pageFooter and pageHeader. To clarify on last detail band page in pageFooter the $PparamHack.contains("detail_end") is true but $PparamHack.contains("summary") is false.

Then in page header use this other flag to determine if to show or not show content.