参数在 jasper 报告中没有绑定

Question

I am trying to generate pdf from jasper reports. But pdf file is generated but parameters are not reflecting in pdf. Here is my code:

firstPage.jrxml file code:

<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="firstPage" pageWidth="595" pageHeight="842" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="9e04b773-6665-446a-837f-863d3d7ce312">
<property name="ireport.zoom" value="1.0"/>
<property name="ireport.x" value="0"/>
<property name="ireport.y" value="11"/>
<parameter name="data" class="java.lang.String"/>
<background>
    <band splitType="Stretch"/>
</background>
<title>
    <band height="79" splitType="Stretch">
        <textField>
            <reportElement x="209" y="27" width="100" height="20" uuid="0fde4029-d805-448f-a443-a436a41865d1"/>
            <textFieldExpression><![CDATA[$P{data}]]></textFieldExpression>
        </textField>
    </band>
</title>
<pageHeader>
    <band height="35" splitType="Stretch"/>
</pageHeader>
<columnHeader>
    <band height="61" splitType="Stretch"/>
</columnHeader>
<detail>
    <band height="190" splitType="Stretch"/>
</detail>
<columnFooter>
    <band height="78" splitType="Stretch"/>
</columnFooter>
<pageFooter>
    <band height="54" splitType="Stretch"/>
</pageFooter>
<summary>
    <band height="42" splitType="Stretch"/>
</summary>

And Spring java code:

Resource resourse = new ClassPathResource("/jasper/firstPage.jasper");
    Resource imgResource = new ClassPathResource("/img/Big_India.jpg");
    Map<String, Object> data = new HashMap<String, Object>();
    data.put("data", "Rks");

    try {
        data.put("imagePath", imgResource.getURL().toString());
        JasperPrint jasperPrint = JasperFillManager.fillReport(resourse.getInputStream(), data);
        JRExporter exporter = new JRPdfExporter();
        exporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint);
        exporter.setParameter(JRExporterParameter.OUTPUT_FILE_NAME, "/home/rakesh/Desktop/ss.pdf");
        exporter.exportReport();
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

And spring file structure is :

Answer 1

Seems you miss a DataSource which is a container storing structured data. Jasper Report engine retrieve data from a DataSource while generating the report.

There are a number of DataSource provided by Jasper such as JRResultSetDataSource , JRBeanCollectionDataSource and JRMapCollectionDataSource . Each can retrieve data from different data source in order to fill the report fields.

In your case, if your do not need to fill data into tables, you can simply use a JREmptyDataSource :

JasperPrint jasperPrint = JasperFillManager.fillReport(resourse.getInputStream(), data, new JREmptyDataSource());

For more details about data source, you can have a look to JasperReports - Data Source Sample