Why Jasper Reports shows empty report in server, b

问题:

I am using Jasper Studio 6.6.0 and Jasper server 7.1.

I have created a simple report with an image from a specified URL.

It generates correctly in Jasper Studio, but in the server it shows empty.

Please refer images attached:

Server Screenshot Jasper Screenshot

回答1:

If you want to show something in the JasperReport without data source or with empty data source then you have two options:

1) Set the When No Data Type property on All Section No Detail option in the Jasper Studio:

In JRXML it can be done by setting whenNoDataType="AllSectionsNoDetail" attribute on the root <jasperReport> element.

2) Or you can move content you want to show when there is no data into No Data band of the report:

In JRXML it it can be done by adding of this:

<noData>
    <band height="110">
        <image>
            <reportElement x="0" y="0" width="240" height="110" uuid="d4b9e59b-896e-4881-92a2-c6707c975312"/>
            <imageExpression><![CDATA["https://my.image.url/getImage?name=penguin"]]></imageExpression>
        </image>
    </band>
</noData>

---

JasperReport renders blank page when there are no data as a default and JasperServer shows The report is empty, so select from above options one you prefer to be able to show the image you want.

回答2:

The best way to do not have the empty page when no data source is provided, is to trick jasper to think there is a data source:

1) Define an Data Adapter (a simple .xml file) and put it in reports folder:

<?xml version="1.0" encoding="UTF-8" ?><emptyDataAdapter class="net.sf.jasperreports.data.empty.EmptyDataAdapterImpl"><name>Data Adapter fake</name><recordCount>1</recordCount></emptyDataAdapter>

2) Link it into the main report:

<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="repor" language="javascript" pageWidth="612" pageHeight="792" whenNoDataType="NoDataSection" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" isFloatColumnFooter="true" uuid="c0eee90e-1b1a-4f34-ad99-1112847752de">
<property name="net.sf.jasperreports.data.adapter" value="EmptyDataAdapter.xml"/>

prefix "repo:" to the value of the property for the data adapter, if the xml is deployed on jasper server.

The attribute "whenNoDataType" will be ignored.

Other details here.