code: List<String> listCompiledClasses(final File classFolder) {
          List<String> classNames = new ArrayList<String>();
          if (!classFolder.exists()) {
              getLog().info("Class folder does not exist; skipping scan");
              return classNames;
          }
          final String extension = ".class";
          final DirectoryScanner directoryScanner = new DirectoryScanner();
          directoryScanner.setBasedir(classFolder);
          directoryScanner.setIncludes(new String[] { "**" + File.separator + "*" + extension });
          directoryScanner.scan();
          String[] files = directoryScanner.getIncludedFiles();
  
          String className;
          for (String file : files) {
              className = file.substring(0, file.length() - extension.length()).replace(File.separator, ".");
              classNames.add(className);
          }
  
          return classNames;
      }
docs: Walks the classFolder and finds all classes
  
  @param classFolder the folder to scan for .class files
  @return the list of available class names