H5Ex_D_Alloc.java

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * All rights reserved.                                                      *
 *                                                                           *
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 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
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 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/************************************************************
  This example shows how to set the space allocation time
  for a dataset.  The program first creates two datasets,
  one with the default allocation time (late) and one with
  early allocation time, and displays whether each has been
  allocated and their allocation size.  Next, it writes data
  to the datasets, and again displays whether each has been
  allocated and their allocation size.
 ************************************************************/

import java.util.EnumSet;
import java.util.HashMap;
import java.util.Map;

import hdf.hdf5lib.H5;
import hdf.hdf5lib.HDF5Constants;

public class H5Ex_D_Alloc {
    private static String FILENAME     = "H5Ex_D_Alloc.h5";
    private static String DATASETNAME1 = "DS1";
    private static String DATASETNAME2 = "DS2";
    private static final int DIM_X     = 4;
    private static final int DIM_Y     = 7;
    private static final int FILLVAL   = 99;
    private static final int RANK      = 2;

    // Values for the status of space allocation
    enum H5D_space_status {
        H5D_SPACE_STATUS_ERROR(-1),
        H5D_SPACE_STATUS_NOT_ALLOCATED(0),
        H5D_SPACE_STATUS_PART_ALLOCATED(1),
        H5D_SPACE_STATUS_ALLOCATED(2);
        private static final Map<Integer, H5D_space_status> lookup = new HashMap<Integer, H5D_space_status>();

        static
        {
            for (H5D_space_status s : EnumSet.allOf(H5D_space_status.class))
                lookup.put(s.getCode(), s);
        }

        private int code;

        H5D_space_status(int space_status) { this.code = space_status; }

        public int getCode() { return this.code; }

        public static H5D_space_status get(int code) { return lookup.get(code); }
    }

    private static void allocation()
    {
        long file_id      = HDF5Constants.H5I_INVALID_HID;
        long filespace_id = HDF5Constants.H5I_INVALID_HID;
        long dataset_id1  = HDF5Constants.H5I_INVALID_HID;
        long dataset_id2  = HDF5Constants.H5I_INVALID_HID;
        long dcpl_id      = HDF5Constants.H5I_INVALID_HID;
        long[] dims       = {DIM_X, DIM_Y};
        int[][] dset_data = new int[DIM_X][DIM_Y];
        int space_status  = 0;
        long storage_size = 0;

        // Initialize the dataset.
        for (int indx = 0; indx < DIM_X; indx++)
            for (int jndx = 0; jndx < DIM_Y; jndx++)
                dset_data[indx][jndx] = FILLVAL;

        // Create a file using default properties.
        try {
            file_id = H5.H5Fcreate(FILENAME, HDF5Constants.H5F_ACC_TRUNC, HDF5Constants.H5P_DEFAULT,
                                   HDF5Constants.H5P_DEFAULT);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Create dataspace. Setting maximum size to NULL sets the maximum
        // size to be the current size.
        try {
            filespace_id = H5.H5Screate_simple(RANK, dims, null);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Create the dataset creation property list, and set the chunk size.
        try {
            dcpl_id = H5.H5Pcreate(HDF5Constants.H5P_DATASET_CREATE);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Set the allocation time to "early". This way we can be sure
        // that reading from the dataset immediately after creation will
        // return the fill value.
        try {
            if (dcpl_id >= 0)
                H5.H5Pset_alloc_time(dcpl_id, HDF5Constants.H5D_ALLOC_TIME_EARLY);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("Creating datasets...");
        System.out.println(DATASETNAME1 + " has allocation time H5D_ALLOC_TIME_LATE");
        System.out.println(DATASETNAME2 + " has allocation time H5D_ALLOC_TIME_EARLY");
        System.out.println();

        // Create the dataset using the dataset default creation property list.
        try {
            if ((file_id >= 0) && (filespace_id >= 0))
                dataset_id1 = H5.H5Dcreate(file_id, DATASETNAME1, HDF5Constants.H5T_NATIVE_INT, filespace_id,
                                           HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT,
                                           HDF5Constants.H5P_DEFAULT);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Create the dataset using the dataset creation property list.
        try {
            if ((file_id >= 0) && (filespace_id >= 0) && (dcpl_id >= 0))
                dataset_id2 = H5.H5Dcreate(file_id, DATASETNAME2, HDF5Constants.H5T_NATIVE_INT, filespace_id,
                                           HDF5Constants.H5P_DEFAULT, dcpl_id, HDF5Constants.H5P_DEFAULT);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Retrieve and print space status and storage size for dset1.
        try {
            if (dataset_id1 >= 0)
                space_status = H5.H5Dget_space_status(dataset_id1);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        try {
            if (dataset_id1 >= 0)
                storage_size = H5.H5Dget_storage_size(dataset_id1);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        String the_space = " ";
        if (H5D_space_status.get(space_status) != H5D_space_status.H5D_SPACE_STATUS_ALLOCATED)
            the_space += "not ";
        System.out.println("Space for " + DATASETNAME1 + " has" + the_space + "been allocated.");
        System.out.println("Storage size for " + DATASETNAME1 + " is: " + storage_size + " bytes.");

        // Retrieve and print space status and storage size for dset2.
        try {
            if (dataset_id2 >= 0)
                space_status = H5.H5Dget_space_status(dataset_id2);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        try {
            if (dataset_id2 >= 0)
                storage_size = H5.H5Dget_storage_size(dataset_id2);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        the_space = " ";
        if (H5D_space_status.get(space_status) != H5D_space_status.H5D_SPACE_STATUS_ALLOCATED)
            the_space += "not ";
        System.out.println("Space for " + DATASETNAME2 + " has" + the_space + "been allocated.");
        System.out.println("Storage size for " + DATASETNAME2 + " is: " + storage_size + " bytes.");
        System.out.println();

        System.out.println("Writing data...");
        System.out.println();

        // Write the data to the datasets.
        try {
            if (dataset_id1 >= 0)
                H5.H5Dwrite(dataset_id1, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL,
                            HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data[0]);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        try {
            if (dataset_id2 >= 0)
                H5.H5Dwrite(dataset_id2, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL,
                            HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data[0]);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Retrieve and print space status and storage size for dset1.
        try {
            if (dataset_id1 >= 0)
                space_status = H5.H5Dget_space_status(dataset_id1);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        try {
            if (dataset_id1 >= 0)
                storage_size = H5.H5Dget_storage_size(dataset_id1);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        the_space = " ";
        if (H5D_space_status.get(space_status) != H5D_space_status.H5D_SPACE_STATUS_ALLOCATED)
            the_space += "not ";
        System.out.println("Space for " + DATASETNAME1 + " has" + the_space + "been allocated.");
        System.out.println("Storage size for " + DATASETNAME1 + " is: " + storage_size + " bytes.");

        // Retrieve and print space status and storage size for dset2.
        try {
            if (dataset_id2 >= 0)
                space_status = H5.H5Dget_space_status(dataset_id2);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        try {
            if (dataset_id2 >= 0)
                storage_size = H5.H5Dget_storage_size(dataset_id2);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        the_space = " ";
        if (H5D_space_status.get(space_status) != H5D_space_status.H5D_SPACE_STATUS_ALLOCATED)
            the_space += "not ";
        System.out.println("Space for " + DATASETNAME2 + " has" + the_space + "been allocated.");
        System.out.println("Storage size for " + DATASETNAME2 + " is: " + storage_size + " bytes.");
        System.out.println();

        // End access to the dataset and release resources used by it.
        try {
            if (dcpl_id >= 0)
                H5.H5Pclose(dcpl_id);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        try {
            if (dataset_id1 >= 0)
                H5.H5Dclose(dataset_id1);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        try {
            if (dataset_id2 >= 0)
                H5.H5Dclose(dataset_id2);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        try {
            if (filespace_id >= 0)
                H5.H5Sclose(filespace_id);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

        // Close the file.
        try {
            if (file_id >= 0)
                H5.H5Fclose(file_id);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) { H5Ex_D_Alloc.allocation(); }
}