I found the following surface plot library and was able to succesfully run via "java Example".

The surface plot is then displayed as it should be.

I then try to recompile the Example.Java and ExampleSurfaceModel.java but receive the following error after "javac Example.java" and "javac ExampleSurfaceMode.java".

C:\>javac Example.java
.\ExampleSurfaceModel.java:12: cannot access ISurfacePlotModel
bad class file: .\ISurfacePlotModel.class
class file contains wrong class: org.sf.surfaceplot.ISurfacePlotModel
Please remove or make sure it appears in the correct subdirectory of the classpa
th.
public class ExampleSurfaceModel implements ISurfacePlotModel


The ISurfacePlotModel.class is contained in the "C:\org\sf\surfaceplot\"

Why is the compiler unable to find the ISurfacePlotModel.class file? Is there a problem with the directory structure? I have commented out the package name within Example.java file.

Attached are the files. I would appreciate any help. I am trying to utilize these class files as a starting point but obviously will be unable to change/tweak the original example if I am unable to compile.SurfacePlot.zip