In my project i have updated jasperreports(and other dependent libs) from 3.0.1 to 4.0.2. And jfreechart bar draws incorrectly . It's draws only last value. I make JRDataSource manually and this was working in jasperreports 3.0.1. As a can see while debugging method getFieldValue is executed and its return wright values . But in output report a can see only the last bar . For example if a have pair values(x-y) - 1-10, 2-20, 3-30, 4-40, in report i will only see 4 as x, and 40 as y, only one bar . If its not enough, I can show example code and jrxml file to reproduce bug.