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Diffstat (limited to 'HDF5Examples/JAVA/H5T/H5Ex_T_BitAttribute.java')
| -rw-r--r-- | HDF5Examples/JAVA/H5T/H5Ex_T_BitAttribute.java | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/HDF5Examples/JAVA/H5T/H5Ex_T_BitAttribute.java b/HDF5Examples/JAVA/H5T/H5Ex_T_BitAttribute.java new file mode 100644 index 0000000..5be1b91 --- /dev/null +++ b/HDF5Examples/JAVA/H5T/H5Ex_T_BitAttribute.java @@ -0,0 +1,264 @@ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * + * Copyright by The HDF Group. * + * 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 COPYING file, which can be found at the root of the source code * + * distribution tree, or in https://www.hdfgroup.org/licenses. * + * 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 bitfield + datatypes to an attribute. The program first writes bit + fields to an attribute with a dataspace of DIM0xDIM1, then + closes the file. Next, it reopens the file, reads back + the data, and outputs it to the screen. + ************************************************************/ + +import hdf.hdf5lib.H5; +import hdf.hdf5lib.HDF5Constants; + +public class H5Ex_T_BitAttribute { + private static String FILENAME = "H5Ex_T_BitAttribute.h5"; + private static String DATASETNAME = "DS1"; + private static String ATTRIBUTENAME = "A1"; + private static final int DIM0 = 4; + private static final int DIM1 = 7; + private static final int RANK = 2; + + private static void CreateDataset() + { + long file_id = HDF5Constants.H5I_INVALID_HID; + long dataspace_id = HDF5Constants.H5I_INVALID_HID; + long dataset_id = HDF5Constants.H5I_INVALID_HID; + long attribute_id = HDF5Constants.H5I_INVALID_HID; + long[] dims = {DIM0, DIM1}; + int[][] dset_data = new int[DIM0][DIM1]; + + // Initialize data. + for (int indx = 0; indx < DIM0; indx++) + for (int jndx = 0; jndx < DIM1; jndx++) { + dset_data[indx][jndx] = 0; + dset_data[indx][jndx] |= (indx * jndx - jndx) & 0x03; /* Field "A" */ + dset_data[indx][jndx] |= (indx & 0x03) << 2; /* Field "B" */ + dset_data[indx][jndx] |= (jndx & 0x03) << 4; /* Field "C" */ + dset_data[indx][jndx] |= ((indx + jndx) & 0x03) << 6; /* Field "D" */ + } + + // 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 dataset with a scalar dataspace. + try { + dataspace_id = H5.H5Screate(HDF5Constants.H5S_SCALAR); + if (dataspace_id >= 0) { + dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id, + HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, + HDF5Constants.H5P_DEFAULT); + H5.H5Sclose(dataspace_id); + dataspace_id = HDF5Constants.H5I_INVALID_HID; + } + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create dataspace. Setting maximum size to NULL sets the maximum + // size to be the current size. + try { + dataspace_id = H5.H5Screate_simple(RANK, dims, null); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create the attribute and write the array data to it. + try { + if ((dataset_id >= 0) && (dataspace_id >= 0)) + attribute_id = + H5.H5Acreate(dataset_id, ATTRIBUTENAME, HDF5Constants.H5T_STD_B8BE, dataspace_id, + HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Write the dataset. + try { + if (attribute_id >= 0) + H5.H5Awrite(attribute_id, HDF5Constants.H5T_NATIVE_B8, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // End access to the dataset and release resources used by it. + try { + if (attribute_id >= 0) + H5.H5Aclose(attribute_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (dataset_id >= 0) + H5.H5Dclose(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Terminate access to the data space. + try { + if (dataspace_id >= 0) + H5.H5Sclose(dataspace_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 ReadDataset() + { + long file_id = HDF5Constants.H5I_INVALID_HID; + long dataspace_id = HDF5Constants.H5I_INVALID_HID; + long dataset_id = HDF5Constants.H5I_INVALID_HID; + long attribute_id = HDF5Constants.H5I_INVALID_HID; + long[] dims = {DIM0, DIM1}; + int[][] dset_data; + + // 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(); + } + + try { + if (dataset_id >= 0) + attribute_id = H5.H5Aopen_by_name(dataset_id, ".", ATTRIBUTENAME, HDF5Constants.H5P_DEFAULT, + HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Get dataspace and allocate memory for read buffer. + try { + if (attribute_id >= 0) + dataspace_id = H5.H5Aget_space(attribute_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (dataspace_id >= 0) + H5.H5Sget_simple_extent_dims(dataspace_id, dims, null); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Allocate array of pointers to two-dimensional arrays (the + // elements of the dataset. + dset_data = new int[(int)dims[0]][(int)(dims[1])]; + + // Read data. + try { + if (attribute_id >= 0) + H5.H5Aread(attribute_id, HDF5Constants.H5T_NATIVE_B8, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Output the data to the screen. + System.out.println(ATTRIBUTENAME + ":"); + for (int indx = 0; indx < dims[0]; indx++) { + System.out.print(" ["); + for (int jndx = 0; jndx < dims[1]; jndx++) { + System.out.print("{" + (dset_data[indx][jndx] & 0x03) + ", "); + System.out.print(((dset_data[indx][jndx] >> 2) & 0x03) + ", "); + System.out.print(((dset_data[indx][jndx] >> 4) & 0x03) + ", "); + System.out.print(((dset_data[indx][jndx] >> 6) & 0x03) + "}"); + } + System.out.println("]"); + } + System.out.println(); + + // End access to the dataset and release resources used by it. + try { + if (attribute_id >= 0) + H5.H5Aclose(attribute_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (dataset_id >= 0) + H5.H5Dclose(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Terminate access to the data space. + try { + if (dataspace_id >= 0) + H5.H5Sclose(dataspace_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_T_BitAttribute.CreateDataset(); + // Now we begin the read section of this example. Here we assume + // the dataset and array have the same name and rank, but can have + // any size. Therefore we must allocate a new array to read in + // data using malloc(). + H5Ex_T_BitAttribute.ReadDataset(); + } +} |