/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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 string datatypes to an attribute. The program first writes strings to an attribute with a dataspace of DIM0, then closes the file. Next, it reopens the file, reads back the data, and outputs it to the screen. ************************************************************/ package examples.datatypes; import hdf.hdf5lib.H5; import hdf.hdf5lib.HDF5Constants; public class H5Ex_T_StringAttribute { private static String FILENAME = "H5Ex_T_StringAttribute.h5"; private static String DATASETNAME = "DS1"; private static String ATTRIBUTENAME = "A1"; private static final int DIM0 = 4; private static final int SDIM = 8; private static final int RANK = 1; private static void CreateDataset() { long file_id = HDF5Constants.H5I_INVALID_HID; long memtype_id = HDF5Constants.H5I_INVALID_HID; long filetype_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 }; byte[][] dset_data = new byte[DIM0][SDIM]; StringBuffer[] str_data = { new StringBuffer("Parting"), new StringBuffer("is such"), new StringBuffer("sweet"), new StringBuffer("sorrow.") }; // 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 file and memory datatypes. For this example we will save // the strings as FORTRAN strings, therefore they do not need space // for the null terminator in the file. try { filetype_id = H5.H5Tcopy(HDF5Constants.H5T_FORTRAN_S1); if (filetype_id >= 0) H5.H5Tset_size(filetype_id, SDIM - 1); } catch (Exception e) { e.printStackTrace(); } try { memtype_id = H5.H5Tcopy(HDF5Constants.H5T_C_S1); if (memtype_id >= 0) H5.H5Tset_size(memtype_id, SDIM); } 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. try { if ((dataset_id >= 0) && (dataspace_id >= 0) && (filetype_id >= 0)) attribute_id = H5.H5Acreate(dataset_id, ATTRIBUTENAME, filetype_id, dataspace_id, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT); } catch (Exception e) { e.printStackTrace(); } // Write the data to the dataset. try { for (int indx = 0; indx < DIM0; indx++) { for (int jndx = 0; jndx < SDIM; jndx++) { if (jndx < str_data[indx].length()) dset_data[indx][jndx] = (byte) str_data[indx].charAt(jndx); else dset_data[indx][jndx] = 0; } } if ((attribute_id >= 0) && (memtype_id >= 0)) H5.H5Awrite(attribute_id, memtype_id, 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(); } // Terminate access to the file type. try { if (filetype_id >= 0) H5.H5Tclose(filetype_id); } catch (Exception e) { e.printStackTrace(); } // Terminate access to the mem type. try { if (memtype_id >= 0) H5.H5Tclose(memtype_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 filetype_id = HDF5Constants.H5I_INVALID_HID; long memtype_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 sdim = 0; long[] dims = { DIM0 }; byte[][] dset_data; StringBuffer[] str_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 the datatype and its size. try { if (attribute_id >= 0) filetype_id = H5.H5Aget_type(attribute_id); if (filetype_id >= 0) { sdim = H5.H5Tget_size(filetype_id); sdim++; // Make room for null terminator } } 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 space for data. dset_data = new byte[(int) dims[0]][(int)sdim]; str_data = new StringBuffer[(int) dims[0]]; // Create the memory datatype. try { memtype_id = H5.H5Tcopy(HDF5Constants.H5T_C_S1); if (memtype_id >= 0) H5.H5Tset_size(memtype_id, sdim); } catch (Exception e) { e.printStackTrace(); } // Read data. try { if ((attribute_id >= 0) && (memtype_id >= 0)) H5.H5Aread(attribute_id, memtype_id, dset_data); byte[] tempbuf = new byte[(int)sdim]; for (int indx = 0; indx < (int) dims[0]; indx++) { for (int jndx = 0; jndx < sdim; jndx++) { tempbuf[jndx] = dset_data[indx][jndx]; } str_data[indx] = new StringBuffer(new String(tempbuf).trim()); } } catch (Exception e) { e.printStackTrace(); } // Output the data to the screen. for (int indx = 0; indx < dims[0]; indx++) { System.out.println(DATASETNAME + " [" + indx + "]: " + str_data[indx]); } 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(); } // Terminate access to the file type. try { if (filetype_id >= 0) H5.H5Tclose(filetype_id); } catch (Exception e) { e.printStackTrace(); } // Terminate access to the mem type. try { if (memtype_id >= 0) H5.H5Tclose(memtype_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_StringAttribute.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_StringAttribute.ReadDataset(); } }