When creating reports with JasperReports, one of the most daunting and error prone tasks is creating the JRXML XML definition file. iReport is an open source Report Designer that aids the developer with that task. It allows designing the report visually, and offers a preview tool. Reports can be previewed in JasperReport's native format, PDF, HTML, XLS, CSV and many other formats. iReport is a stand alone Swing application.
iReport is distributed as a single zip file, to install iReport, all that is needed is to unzip the file on any directory. To start iReport, simply execute iReport.bat under Microsoft Windows, or iReport.sh under Unix-like operating systems like Linux or Mac OS X.
Creating a JasperReports report with iReport is very simple, all that is needed to do is go to File -> New Document, the default settings for a new document are appropriate for most reports. iReports provides us with predefined areas for the report title, the page header, column header, detail area, column footer, page footer and last page footer. To add labels to the report, all that is needed is clicking on the "T" icon at the top of the screen, then define the area where the text will be displayed by outlining it with the mouse pointer. Adding fields to the report is equally easy, all that is needed is to click on the "F" icon at the top of the screen, and define the area in the report where the field will be displayed by outlining it with the mouse pointer. Speaking of fields, iReport can be configured to create fields automatically from a database query. Several Relational Database Management Systems (RDBMS) are supported, including, but not limited to Oracle, Sybase, SQL server, MySQL and PostgreSQL. JDBC drivers for the appropriate RDBMS are required. Reports can be previewed in PDF, XLS, RTF and several other formats.
iReport is an excellent tool that greatly speeds up the task of designing reports for JasperReports. The only drawback I see is that there is not much documentation available, however there are some tutorials online that fill this void (see Resources). If you are using JasperReports as your reporting tool and you are still coding the JRXML files by hand, do yourself a favor and download iReport, it will make your life a lot simpler.