I have downloaded the latest version of JFreeChart (1.0.14) and want to start using it. I only have imported standard Java packages like java.io.* before and never dealt with 3rd party libraries. What do I need to tell jGRASP so it knows about and can access the JFreeChart library? I have tried to import it like this import org.jfree.chart.ChartFactory; but getting the following error java:1: package org.jfree.chart does not exist.
You have to add a library's jar file into both compile-time and run-time CLASSPATH. In jGRASP you can do it through "Settings > PATH/CLASSPATH > Workspace" dialog. See HOWTO, Control Panel and Settings for more details.
By adding both jar libraries:
\jfreechart-1.0.14\lib\jfreechart-1.0.14.jar and
\jfreechart-1.0.14\lib\jcommon-1.0.17.jar
into CLASSPATH, you will be able to use the library straight forward.
来源：https://stackoverflow.com/questions/9028516/how-to-get-started-with-jfreechart