First of all, the records are shown in the table by table component but not in the report one.
The results looks like this:
YEARS MONTHS SUMMONTH SUMQUARTER
----- ------ -------- ----------
2009 Jan 130984 432041
Feb 146503
Mar 154554
Apr 147917 435150
May 131822
Jun 155411
Jul 144000 424806
Aug 130369
Sep 150437
Oct 112137 400114
Nov 152057
Dec 135920
=====================================
Jan-Dec 1692111
=====================================
2010 Jan 139927 417564
Feb 154940
Mar 122697
Apr 163257 413305
May 124999
Jun 125049
Jul 145127 427612
Aug 138804
Sep 143681
Oct 143398 406381
Nov 125351
Dec 137632
=====================================
Jan-Dec 1664862
=====================================
The sumquarter column shows the sum of each quarter in year.
They are not printed when it repeated the value of the field.
The question is how to group the column of sumquarter, so that the first printed repeated value in each row to join the next repeated value to become a single cell until it meets the non-repeated value?
You can simply see it in an image. Below is the image that the table shows and the solution that I preferred is to group those 3 months of sum into a single cell.
Here is the image:
You can use this sample:
<?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="year_sum_quarter" language="groovy" pageWidth="595" pageHeight="842" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20">
<property name="ireport.zoom" value="1.0"/>
<property name="ireport.x" value="0"/>
<property name="ireport.y" value="0"/>
<queryString>
<![CDATA[]]>
</queryString>
<field name="year" class="java.lang.Integer"/>
<field name="month" class="java.lang.String"/>
<field name="sum" class="java.lang.Integer"/>
<field name="q" class="java.lang.Integer"/>
<variable name="yearSum" class="java.lang.Integer" resetType="Group" resetGroup="yearGroup" calculation="Sum">
<variableExpression><![CDATA[$F{sum}]]></variableExpression>
</variable>
<variable name="qSum" class="java.lang.Integer" resetType="Group" resetGroup="quaterGroup" calculation="Sum">
<variableExpression><![CDATA[$F{sum}]]></variableExpression>
</variable>
<group name="yearGroup">
<groupExpression><![CDATA[$F{year}]]></groupExpression>
<groupFooter>
<band height="20">
<textField>
<reportElement x="100" y="0" width="100" height="20"/>
<box leftPadding="10">
<topPen lineWidth="1.0"/>
<leftPen lineWidth="0.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="0.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA["Jan-Dec, " + $F{year}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="200" y="0" width="100" height="20"/>
<box leftPadding="0">
<topPen lineWidth="1.0"/>
<leftPen lineWidth="0.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="0.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA[$V{yearSum}]]></textFieldExpression>
</textField>
<staticText>
<reportElement x="0" y="0" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="0.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[]]></text>
</staticText>
<staticText>
<reportElement x="300" y="0" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="0.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[]]></text>
</staticText>
</band>
</groupFooter>
</group>
<group name="quaterGroup">
<groupExpression><![CDATA[$F{year} + $F{q}]]></groupExpression>
</group>
<columnHeader>
<band height="50">
<staticText>
<reportElement x="100" y="30" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[Month]]></text>
</staticText>
<staticText>
<reportElement x="0" y="30" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[Year]]></text>
</staticText>
<staticText>
<reportElement x="200" y="30" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[Month Sum]]></text>
</staticText>
<staticText>
<reportElement x="300" y="30" width="100" height="20"/>
<box>
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[Quarter Sum]]></text>
</staticText>
</band>
</columnHeader>
<detail>
<band height="20" splitType="Stretch">
<staticText>
<reportElement x="300" y="0" width="100" height="20"/>
<box>
<topPen lineWidth="0.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="0.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[]]></text>
</staticText>
<staticText>
<reportElement x="0" y="0" width="100" height="20"/>
<box>
<topPen lineWidth="0.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="0.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement textAlignment="Center" verticalAlignment="Middle">
<font isBold="true" isItalic="true"/>
</textElement>
<text><![CDATA[]]></text>
</staticText>
<textField>
<reportElement x="0" y="0" width="100" height="20">
<printWhenExpression><![CDATA[$V{yearGroup_COUNT} == 1]]></printWhenExpression>
</reportElement>
<box leftPadding="10">
<topPen lineWidth="0.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="0.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA[$F{year}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="200" y="0" width="100" height="20"/>
<box leftPadding="10">
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA[$F{sum}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="100" y="0" width="100" height="20"/>
<box leftPadding="10">
<topPen lineWidth="1.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="1.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA[$F{month}]]></textFieldExpression>
</textField>
<textField evaluationTime="Group" evaluationGroup="quaterGroup" isBlankWhenNull="false">
<reportElement stretchType="RelativeToBandHeight" isPrintRepeatedValues="false" x="300" y="0" width="100" height="20" printWhenGroupChanges="quaterGroup">
<printWhenExpression><![CDATA[$V{quaterGroup_COUNT} == 1]]></printWhenExpression>
</reportElement>
<box leftPadding="10">
<topPen lineWidth="0.0"/>
<leftPen lineWidth="1.0"/>
<bottomPen lineWidth="0.0"/>
<rightPen lineWidth="1.0"/>
</box>
<textElement/>
<textFieldExpression><![CDATA[$V{qSum}]]></textFieldExpression>
</textField>
<line>
<reportElement x="300" y="0" width="100" height="1" printWhenGroupChanges="quaterGroup">
<printWhenExpression><![CDATA[$V{quaterGroup_COUNT} == 1]]></printWhenExpression>
</reportElement>
</line>
</band>
</detail>
</jasperReport>
The result will be (in pdf format):
In this sample I've used two elements in the Detail band for the Year column:
one textField with only vertical borders and with printWhenExpression: "$V{yearGroup_COUNT} == 1" property (I'm show it only once for the whole yearGroup) and one staticText without any text and with only vertical borders.
I've used three elements in the Detail band for the Quarter Sum column:
one textField with only vertical borders and with printWhenExpression: "$V{quaterGroup_COUNT} == 1" property (I'm show it only once for the whole quaterGroup), one staticText without any text and with only vertical borders and the line element for drawing horizontal border with printWhenExpression: "$V{quaterGroup_COUNT} == 1" property.
来源：https://stackoverflow.com/questions/9798399/group-several-same-value-field-into-a-single-cell