Can't create a list field with JSON Datasource

[inanutshellus]

 

Given a simple JSON datasource, like so: 

 

 

    {

      "Customers": [

        {

          "ContactName": "John Doe",

          "Orders": [

            { "OrderID": 100 },

            { "OrderID": 101 }

          ]

        }, {

          "ContactName": "Jane Smith",

          "Orders": [

            { "OrderID": 102 },

            { "OrderID": 103 },

            { "OrderID": 104 }

          ]

        }

      ]

    }

 

 

I can't seem to declare the field "Orders" as a List. 

 

It blows up like so: 

 

 

    Error filling print... Unable to get value for field 'Orders' of class 'java.util.List'

    net.sf.jasperreports.engine.JRException: Unable to get value for field 'Orders' of class 'java.util.List'

         at net.sf.jasperreports.engine.data.JsonDataSource.getFieldValue(JsonDataSource.java:233)

         at net.sf.jasperreports.engine.fill.JRFillDataset.setOldValues(JRFillDataset.java:1317)

    [...]

         at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997) Caused by: net.sf.jasperreports.engine.JRException: Field 'Orders' is of class 'java.util.List' and cannot be converted

         at net.sf.jasperreports.engine.data.JsonDataSource.getFieldValue(JsonDataSource.java:230)

         ... 13 more

 

 

 

To reproduce it, load the following JRXML into iReport, and try to run it with the above datasource. Notice I'm not even using the Orders!

 

 

    <?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="deepJsonTest" language="groovy" pageWidth="612" pageHeight="792" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="5f9dde08-ee77-4cc0-bfe5-199306a133a9">

        <property name="ireport.zoom" value="1.0"/>

        <property name="ireport.x" value="0"/>

        <property name="ireport.y" value="0"/>

        <queryString language="json">

            <![CDATA[Customers]]>

        </queryString>

        <field name="ContactName" class="java.lang.String">

            <fieldDescription><![CDATA[ContactName]]></fieldDescription>

        </field>

        <field name="Orders" class="java.util.List">

            <fieldDescription><![CDATA[Orders]]></fieldDescription>

        </field>

        <detail>

            <band height="153" splitType="Stretch">

                <textField>

                    <reportElement uuid="923b522c-825e-4ebf-a3be-42802544f48f" x="0" y="0" width="100" height="20"/>

                    <textElement/>

                    <textFieldExpression><![CDATA[$F{ContactName}]]></textFieldExpression>

                </textField>

            </band>

        </detail>

    </jasperReport>

 

[ecanaveras]

Hi..

 

Try java.util.Collection

 

Regards

[inanutshellus]

Also doesn't work.

[inanutshellus]

Looking in the source, turns out they don't support lists, so you can't do subdatasets without a flat file (which is how the subdataset is done in the Jasper Reports example).

However, one of my devs has dropped a patch here:

http://community.jaspersoft.com/jasperreports-library/issues/2500-0

If you have a JSON List, declare it as an InputStream and send it to your subdataset. All we need now is someone to review the patch.