JFreeChart is a framework for the Java programming language with which to easily complex diagrams can be created. The software supports various chart types such as column charts, bar charts, pie charts, Gantt charts and histograms. Even a simple Export of graphics as a PNG or JPEG is possible.
The JFreeChart project was started in 2000 by David Gilbert, and is headed by him. But it did a smaller contributions other developers. The project is mainly supported financially by Object Refinery Limited, the company of David Gilbert, who sells documentaries and Consulting around JFreeChart to other companies. This means that on the official website, only the raw javadocs and some screenshots are listed, and no easy -to-use code examples that are provided only to paying customers.
Download counts are constant over 20,000 per month from SourceForge alone JFreeChart has been downloaded more than 3.5 million times. The API is used in several open-source and commercial products; to the known include JBoss and StatCVS to open source, as well as JIRA Chart plugin and NetBeans QA on a commercial basis.