Jasper Reports!

Reporting is always been a necessary feature of any Enterprise organization. Around 20-30% of software applications certainly include basic to advanced reporting.

There are plenty of utilities available to make reporting easy to integrate with any enterprise architecture.

The default choice of reporting tech has been the 'Crystal Reports' especially when microsoft bundled the product with Visual Studio. The Crystal Reports are marked by Business Objects[now acquired by SAP] and costs around $500 per license.

Jasper Reports comes as a Savior of OPEN source equally comprising all features of commerial products and well integrates with Java with good community participation.

JasperReports provides the necessary features to generate dynamic reports, including data retrieval using JDBC (Java Database Connectivity), as well as support for parameters, expressions, variables, and groups. JasperReports also includes advanced features, such as custom data sources, scriptlets, and subreports.

There have been plenty of releases and the current version is 2.0

Lets look at basic architecture and how to generate a simple report with Jasper.

Basic Objects of Jasper:

JasperDesign: Represents a report's definition. In most cases, you create a JasperDesign from an XML report template, though you can also create it programmatically.

JasperReport: Represents a compiled JasperDesign. The compilation process verifies the report design and compiles the design into a JasperReport object.

JasperPrint: Represents a generated report. You create a JasperPrint from a JasperReport through the fill process in which a report is populated with data from a data source.

JasperManager:
The JasperReports API's flexibility lets you load JasperDesign, JasperReport, and JasperPrint objects from a file or a stream, and also lets you create these objects programmatically. You can print reports to a printer, an image, or a PDF file. The JasperReports library includes a facade class, dori.jasper.engine.JasperManager, with methods that facilitate loading, compiling, filling, and printing reports.

Generating basic Report:


// First, load JasperDesign from XML and compile it into JasperReport

JasperDesign jasperDesign = JasperManager.loadXmlDesign("BasicReport.xml");

JasperReport jasperReport = JasperManager.compileReport(jasperDesign);

// Second, create a map of parameters to pass to the report.
Map parameters = new HashMap();
parameters.put("ReportTitle", "Basic JasperReport");
parameters.put("MaxSalary", new Double(25000.00));

// Third, get a database connection
Connection conn = Database.getConnection();

// Fourth, create JasperPrint using fillReport() method
JasperPrint jasperPrint = JasperManager.fillReport(jasperReport,
parameters, conn);
// You can use JasperPrint to create PDF
JasperManager.printReportToPdfFile(jasperPrint, "BasicReport.pdf");
// Or to view report in the JasperViewer
JasperViewer.viewReport(jasperPrint);


Another way to build report..


//Get the JRXML file
String fileName = lookUp(module);
InputStream templatesAsStream = loadTemplateAsStream(fileName);
JasperReport jasperReport = JasperCompileManager.compileReport(templatesAsStream);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport,
builder.build(object), new JREmptyDataSource());

byte[] bytes = JasperExportManager.exportReportToPdf(jasperPrint);


Sample JRML file

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE jasperReport PUBLIC "-//JasperReports//DTD Report Design//EN"
 "http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">
<jasperReport name="BasicReport" >
  <parameter name="Title" class="java.lang.String"/>
  <queryString><![CDATA[select name, cost from product]]></queryString>
  <field name="NAME" class="java.lang.String"/>
  <field name="COST" class="java.lang.Double"/>
  <title>
    <band height="50">
      <textField>
        <reportElement x="0" y="0" width="200" height="50" />      
        <textFieldExpression class="java.lang.String">$P{Title}</textFieldExpression>
      </textField>
    </band>
  </title>
  <pageHeader>
    <band>
    </band>
  </pageHeader>
  <columnHeader>
    <band height="20">
      <staticText>
        <reportElement x="180" y="0" width="180" height="20"/>
        <textElement>
          <font isUnderline="true"/>
        </textElement>
        <text><![CDATA[NAME]]></text>
      </staticText>
      <staticText>
        <reportElement x="360" y="0" width="180" height="20"/>
        <textElement>
          <font isUnderline="true"/>
        </textElement>
        <text><![CDATA[COST]]></text>
      </staticText>
    </band>
  </columnHeader>
  <detail>
    <band height="20">
      <textField>
        <reportElement x="180" y="0" width="180" height="20"/>                 
        <textFieldExpression class="java.lang.String"><![CDATA[$F{NAME}]]></textFieldExpression>
      </textField>
      <textField pattern="0.00">
        <reportElement x="360" y="0" width="180" height="20"/>                 
        <textFieldExpression class="java.lang.Double"><![CDATA[$F{COST}]]></textFieldExpression>
      </textField>
    </band>
  </detail>
  <columnFooter>
    <band>
    </band>
  </columnFooter>
  <pageFooter>
    <band height="15">
      <staticText>
        <reportElement x="0" y="0" width="40" height="15"/>
        <textElement/>
        <text><![CDATA[Page:]]></text>
      </staticText>
      <textField>
        <reportElement x="40" y="0" width="100" height="15"/>
        <textElement/>
        <textFieldExpression class="java.lang.Integer"><![CDATA[$V{PAGE_NUMBER}]]></textFieldExpression>
      </textField>
    </band>
  </pageFooter>
  <summary>
    <band>
    </band>
  </summary>
</jasperReport>












More intro...
http://www.jasperforge.org/jaspersoft/opensource/business_intelligence/jasperreports/