The java.lang.NoClassDefFoundError means Java cannot find a class. If the class name is from ChartDirector, and the error occurs during compile time, it is probably because the "ChartDirector.jar" (or "ChartDirector_s.jar") has not been included in the project.
Have you add "ChartDirector.jar" (or "ChartDirector_s.jar") as a dependency in your project?
If the project can compile normally, but the error occurs when you try to run the project, it may be because your project type requires the "ChartDirector.jar" to be copied to a certain location (eg. JSP or J2EE web applications may require the JAR file to be copied to the WEB-INF directory). The exact details depends on your application type.