Layer

protected final String id;
protected final LayerType type;
protected LayerProperties properties;

Dluid use layer for saving some parameter to dl4j layer. And it also has the type of itself. Layer id is unique value in Dluid. By this value, dluid can search layer.

Layer properties

public class LayerProperties {
    // common properties
    private int[] inputSize;
    private int[] outputSize;
    private Dimension inputDimension;
    private Dimension outputDimension;
    private BiasInitializer biasInitializer;
    private WeightInitializer weightInitializer;
    private ActivationWrapper activationFunction;
    private double dropout;

    // for convolution type
    private int[] kernelSize;
    private int[] strideSize;
    private int[] paddingSize;

    // for output type
    private LossFunctionWrapper lossFunction;

    // for pooling layer
    private PoolingTypeWrapper poolingType;
}

Dluid save parameters for dl4j in one class without distinction. That is LayerProperties class.