A Tutorial on Reporting in JAVA using JasperReports, iReport and JFreeChart by Onur Derin

A report is a nicely formatted way of presenting the data that you have entered. Reports are all about querying a database and displaying the results in a nice format. Data in the database may be displayed just as is, that is, in hundreds of pages. However, most of the time, reports are used to grasp information out of a bunch of data. This is mainly done by charts which are graphical representations of information. When the data is processed to fill out a report, calculations are done over the specific fields of the entries. The results appear as bars or pies in a chart or as text at the end of the report