/************************************************************
  This example shows how to read and write data to a
  dataset.  The program first writes integers to a dataset
  with dataspace dimensions of DIM_XxDIM_Y, then closes the
  file.  Next, it reopens the file, reads back the data, and
  outputs it to the screen.
 ************************************************************/
package examples.datasets;

import ncsa.hdf.object.Dataset;
import ncsa.hdf.object.Datatype;
import ncsa.hdf.object.FileFormat;
import ncsa.hdf.object.h5.H5Datatype;
import ncsa.hdf.object.h5.H5File;

public class H5ObjectEx_D_ReadWrite {
	private static String FILENAME = "H5ObjectEx_D_ReadWrite.h5";
	private static String DATASETNAME = "DS1";
	private static final int DIM_X = 4;
	private static final int DIM_Y = 7;
    private static final int DATATYPE_SIZE = 4;

	private static void WriteDataset() {
        H5File file = null;
        Dataset dset = null;
		long[] dims = { DIM_X, DIM_Y };
		int[][] dset_data = new int[DIM_X][DIM_Y];
        final H5Datatype typeInt = new H5Datatype(Datatype.CLASS_INTEGER,
                DATATYPE_SIZE, Datatype.ORDER_LE, -1);

		// Initialize data.
		for (int indx = 0; indx < DIM_X; indx++)
			for (int jndx = 0; jndx < DIM_Y; jndx++)
				dset_data[indx][jndx] = indx * jndx - jndx;

		// Create a new file using default properties.
		try {
            file = new H5File(FILENAME, FileFormat.CREATE);
            file.open();
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		// Create the dataset. We will use all default properties for this example.
        // And write the data to the dataset.
		try {
            dset = file.createScalarDS("/" + DATASETNAME, null, typeInt,
                    dims, null, null, 0,
                    dset_data);
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		// Close the file.
		try {
            file.close();
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}

	private static void ReadDataset() {
        H5File file = null;
        Dataset dset = null;
		int[] dset_data = new int[DIM_X*DIM_Y];

		// Open file using the default properties.
		try {
            file = new H5File(FILENAME, FileFormat.READ);
            file.open();
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		// Open dataset using the default properties.
		try {
            dset = (Dataset) file.get(DATASETNAME);
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		// Read the data using the default properties.
		try {
            dset.init();
            dset_data = (int[]) dset.getData();
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		// Output the data to the screen.
		System.out.println(DATASETNAME + ":");
		for (int indx = 0; indx < DIM_X; indx++) {
			System.out.print(" [ ");
			for (int jndx = 0; jndx < DIM_Y; jndx++)
				System.out.print(dset_data[indx*DIM_Y+jndx] + " ");
			System.out.println("]");
		}
		System.out.println();

		// Close the file.
		try {
            file.close();
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}

	public static void main(String[] args) {
		H5ObjectEx_D_ReadWrite.WriteDataset();
		H5ObjectEx_D_ReadWrite.ReadDataset();
	}

}