code: public InputPreProcessor getInputPreprocessor(InputType... inputType) throws InvalidKerasConfigurationException {
          if (inputType.length > 1)
              throw new InvalidKerasConfigurationException(
                      "Keras GlobalPooling layer accepts only one input (received " + inputType.length + ")");
          InputPreProcessor preprocessor;
          if (inputType[0].getType() == InputType.Type.FF && this.dimensions.length == 1) {
              preprocessor = new FeedForwardToRnnPreProcessor();
          } else {
              preprocessor = this.getGlobalPoolingLayer().getPreProcessorForInputType(inputType[0]);
          }
          return preprocessor;
      }
docs: Gets appropriate DL4J InputPreProcessor for given InputTypes.
  
  @param inputType Array of InputTypes
  @return DL4J InputPreProcessor
  @throws InvalidKerasConfigurationException Invalid Keras config
  @see org.deeplearning4j.nn.conf.InputPreProcessor