code: Object getClassInstance() throws UtilEvalError {
          if (this.classInstance != null)
              return this.classInstance;
          if (this.classStatic != null
          // || (getParent()!=null && getParent().classStatic != null)
         )
              throw new UtilEvalError(
                      "Can't refer to class instance from static context.");
          else
              throw new InterpreterError(
                      "Can't resolve class instance 'this' in: " + this);
      }
docs: Gets the class instance.
  @return the class instance
  @throws UtilEvalError the util eval error