[svn-r29226] HDFFV-9552: merge in java code.

1 files changed, 347 insertions, 0 deletions

diff --git a/java/examples/datasets/H5Ex_D_Checksum.java b/java/examples/datasets/H5Ex_D_Checksum.java
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+++ b/java/examples/datasets/H5Ex_D_Checksum.java
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+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/************************************************************
+  This example shows how to read and write data to a dataset
+  using the Fletcher32 checksum filter.  The program first
+  checks if the Fletcher32 filter is available, then if it
+  is it writes integers to a dataset using Fletcher32, then
+  closes the file.  Next, it reopens the file, reads back
+  the data, checks if the filter detected an error and
+  outputs the type of filter and the maximum value in the
+  dataset to the screen.
+ ************************************************************/
+package examples.datasets;
+
+import java.util.EnumSet;
+import java.util.HashMap;
+import java.util.Map;
+
+import hdf.hdf5lib.H5;
+import hdf.hdf5lib.HDF5Constants;
+
+public class H5Ex_D_Checksum {
+    private static String FILENAME = "H5Ex_D_Checksum.h5";
+    private static String DATASETNAME = "DS1";
+    private static final int DIM_X = 32;
+    private static final int DIM_Y = 64;
+    private static final int CHUNK_X = 4;
+    private static final int CHUNK_Y = 8;
+    private static final int RANK = 2;
+    private static final int NDIMS = 2;
+
+    // Values for the status of space allocation
+    enum H5Z_filter {
+        H5Z_FILTER_ERROR(-1), H5Z_FILTER_NONE(0), H5Z_FILTER_DEFLATE(1), H5Z_FILTER_SHUFFLE(2), H5Z_FILTER_FLETCHER32(3), H5Z_FILTER_SZIP(
+                4), H5Z_FILTER_NBIT(5), H5Z_FILTER_SCALEOFFSET(6), H5Z_FILTER_RESERVED(256), H5Z_FILTER_MAX(65535);
+        private static final Map<Integer, H5Z_filter> lookup = new HashMap<Integer, H5Z_filter>();
+
+        static {
+            for (H5Z_filter s : EnumSet.allOf(H5Z_filter.class))
+                lookup.put(s.getCode(), s);
+        }
+
+        private int code;
+
+        H5Z_filter(int layout_type) {
+            this.code = layout_type;
+        }
+
+        public int getCode() {
+            return this.code;
+        }
+
+        public static H5Z_filter get(int code) {
+            return lookup.get(code);
+        }
+    }
+
+    private static boolean checkFletcher32Filter() {
+        try {
+            int available = H5.H5Zfilter_avail(H5Z_filter.H5Z_FILTER_FLETCHER32.getCode());
+            if (available == 0) {
+                System.out.println("N-Bit filter not available.");
+                return false;
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        try {
+            int filter_info = H5.H5Zget_filter_info(HDF5Constants.H5Z_FILTER_FLETCHER32);
+            if (((filter_info & HDF5Constants.H5Z_FILTER_CONFIG_ENCODE_ENABLED) == 0)
+                    || ((filter_info & HDF5Constants.H5Z_FILTER_CONFIG_DECODE_ENABLED) == 0)) {
+                System.out.println("N-Bit filter not available for encoding and decoding.");
+                return false;
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+        return true;
+    }
+
+    private static void writeChecksum() {
+        long file_id = -1;
+        long filespace_id = -1;
+        long dataset_id = -1;
+        long dcpl_id = -1;
+        long[] dims = { DIM_X, DIM_Y };
+        long[] chunk_dims = { CHUNK_X, CHUNK_Y };
+        int[][] dset_data = new int[DIM_X][DIM_Y];
+
+        // 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_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, add the N-Bit filter.
+        try {
+            dcpl_id = H5.H5Pcreate(HDF5Constants.H5P_DATASET_CREATE);
+            if (dcpl_id >= 0) {
+                H5.H5Pset_fletcher32(dcpl_id);
+                // Set the chunk size.
+                H5.H5Pset_chunk(dcpl_id, NDIMS, chunk_dims);
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Create the dataset.
+        try {
+            if ((file_id >= 0) && (filespace_id >= 0) && (dcpl_id >= 0))
+                dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, filespace_id,
+                        HDF5Constants.H5P_DEFAULT, dcpl_id, HDF5Constants.H5P_DEFAULT);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Write the data to the dataset.
+        try {
+            if (dataset_id >= 0)
+                H5.H5Dwrite(dataset_id, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, HDF5Constants.H5S_ALL,
+                        HDF5Constants.H5P_DEFAULT, dset_data);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // 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_id >= 0)
+                H5.H5Dclose(dataset_id);
+        }
+        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();
+        }
+    }
+
+    private static void readChecksum() {
+        long file_id = -1;
+        long dataset_id = -1;
+        long dcpl_id = -1;
+        int[][] dset_data = new int[DIM_X][DIM_Y];
+
+        // Open an existing file.
+        try {
+            file_id = H5.H5Fopen(FILENAME, HDF5Constants.H5F_ACC_RDONLY, HDF5Constants.H5P_DEFAULT);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Open an existing dataset.
+        try {
+            if (file_id >= 0)
+                dataset_id = H5.H5Dopen(file_id, DATASETNAME, HDF5Constants.H5P_DEFAULT);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Retrieve the dataset creation property list.
+        try {
+            if (dataset_id >= 0)
+                dcpl_id = H5.H5Dget_create_plist(dataset_id);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Retrieve and print the filter type. Here we only retrieve the
+        // first filter because we know that we only added one filter.
+        try {
+            if (dcpl_id >= 0) {
+                // Java lib requires a valid filter_name object and cd_values
+                int[] flags = { 0 };
+                long[] cd_nelmts = { 1 };
+                int[] cd_values = { 0 };
+                String[] filter_name = { "" };
+                int[] filter_config = { 0 };
+                int filter_type = -1;
+                filter_type = H5
+                        .H5Pget_filter(dcpl_id, 0, flags, cd_nelmts, cd_values, 120, filter_name, filter_config);
+                System.out.print("Filter type is: ");
+                switch (H5Z_filter.get(filter_type)) {
+                case H5Z_FILTER_DEFLATE:
+                    System.out.println("H5Z_FILTER_DEFLATE");
+                    break;
+                case H5Z_FILTER_SHUFFLE:
+                    System.out.println("H5Z_FILTER_SHUFFLE");
+                    break;
+                case H5Z_FILTER_FLETCHER32:
+                    System.out.println("H5Z_FILTER_FLETCHER32");
+                    break;
+                case H5Z_FILTER_SZIP:
+                    System.out.println("H5Z_FILTER_SZIP");
+                    break;
+                default:
+                    System.out.println("H5Z_FILTER_ERROR");
+                }
+                System.out.println();
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Read the data using the default properties.
+        try {
+            if (dataset_id >= 0) {
+                int status = H5.H5Dread(dataset_id, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL,
+                        HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data);
+                // Check if the read was successful. Normally we do not perform
+                // error checking in these examples for the sake of clarity, but in
+                // this case we will make an exception because this is how the
+                // fletcher32 checksum filter reports data errors.
+                if (status < 0) {
+                    System.out.print("Dataset read failed!");
+                    try {
+                        if (dcpl_id >= 0)
+                            H5.H5Pclose(dcpl_id);
+                        if (dataset_id >= 0)
+                            H5.H5Dclose(dataset_id);
+                        if (file_id >= 0)
+                            H5.H5Fclose(file_id);
+                    }
+                    catch (Exception e) {
+                        e.printStackTrace();
+                    }
+                    return;
+                }
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        // Find the maximum value in the dataset, to verify that it was read
+        // correctly.
+        int max = dset_data[0][0];
+        for (int indx = 0; indx < DIM_X; indx++) {
+            for (int jndx = 0; jndx < DIM_Y; jndx++)
+                if (max < dset_data[indx][jndx])
+                    max = dset_data[indx][jndx];
+        }
+        // Print the maximum value.
+        System.out.println("Maximum value in " + DATASETNAME + " is: " + max);
+
+        // 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_id >= 0)
+                H5.H5Dclose(dataset_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) {
+        // Check if the Fletcher32 filter is available and can be used for
+        // both encoding and decoding. Normally we do not perform error
+        // checking in these examples for the sake of clarity, but in this
+        // case we will make an exception because this filter is an
+        // optional part of the hdf5 library.
+        // size to be the current size.
+        if (H5Ex_D_Checksum.checkFletcher32Filter()) {
+            H5Ex_D_Checksum.writeChecksum();
+            H5Ex_D_Checksum.readChecksum();
+        }
+    }
+
+}