code: private Cls readClass(String name, String superClass)
              throws KnowledgeSourceReadException {
          Cls cls = this.cm.getCls(name);
          Cls superCls = this.cm.getCls(superClass);
          if (cls != null && cls.hasSuperclass(superCls)) {
              return cls;
          } else {
              return null;
          }
      }
docs: Returns the Cls from Protege if a matching Cls is found with the given
  ancestor
  
  @param name Name of the class to fetch
  @param superClass name of the anscestor
  @return A Cls containing the given class name
  @throws KnowledgeSourceReadException