crosstab in jasper displays only the first column from input json - json

Question

my json is as follows
"values": [
{
"purchase": {
"name":"bags"
},
"weekSpend": [
{
"weekStartDate": 20181105,
"spend":100
},
{
"weekStartDate": 20181112,
"spend":200
}
]
},
{
"purchase": {
"name":"shoes"
},
"weekSpend": [
{
"weekStartDate": 20181105,
"spend":100
},
{
"weekStartDate": 20181112,
"spend":200
}
]
},
]
I want to displayed the grid where rows are
productname and (columns by weekstartdate)
I followed the technique provided in How to show column at Crosstab even the data is absent
However the productname are listed in row but the column are showing only first column.
my data set is as follows
<queryString language="jsonql">
<![CDATA[]]>
</queryString>
<field name="productName" class="java.lang.String">
<property name="net.sf.jasperreports.jsonql.field.expression" value="product.name"/>
<fieldDescription><![CDATA[product.name]]></fieldDescription>
</field>
<field name="weekStartDate" class="java.lang.String[]">
<property name="net.sf.jasperreports.jsonql.field.expression" value="weekSpend.weekStartDate"/>
</field>
<group name="activityDateGroup">
<groupExpression><![CDATA[$F{weekStartDate}]]></groupExpression>
</group>
my crossdata datasource is as follows
<crosstabDataset isDataPreSorted="true">
<dataset>
<datasetRun subDataset="crossTabDataSet" uuid="e7b27508-8a48-4785-a48e-c646249df9a9">
<dataSourceExpression><![CDATA[((net.sf.jasperreports.engine.data.JsonQLDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("..values(#size > 0).*")]]></dataSourceExpression>
</datasetRun>
</dataset>
</crosstabDataset>
and bucketexpression is on weekstartdate.
With these using JsonQL still only the first column is displayed
How do i get list of column based on weekstardate from iterating from rootnode.
i am using jasper studio 6.5.
Thanks
Anjana.

Answer 1

There is an invalid field mapping: weekStartDate to java.lang.String[], that is not supported in JSONQL.
Instead you could have this subDataset expression:
<datasetRun subDataset="crossTabDataSet" uuid="e7b27508-8a48-4785-a48e-c646249df9a9">
<dataSourceExpression><![CDATA[((net.sf.jasperreports.engine.data.JsonQLDataSource)$P{REPORT_DATA_SOURCE}).subDataSource("..values(#size > 0)..weekSpend.*")]]></dataSourceExpression>
</datasetRun>
with these field mappings:
<field name="productName" class="java.lang.String">
<property name="net.sf.jasperreports.jsonql.field.expression" value="^{2}.purchase.name"/>
</field>
<field name="weekStartDate" class="java.lang.Integer">
<property name="net.sf.jasperreports.jsonql.field.expression" value="weekStartDate"/>
</field>