CDataWriter.java

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package org.lightvoting;

import org.bytedeco.javacpp.IntPointer;
import org.bytedeco.javacpp.hdf5;

public final class CDataWriter
{
    // source: https://github.com/bytedeco/javacpp-presets/tree/master/hdf5#the-srcmainjavah5tutrcmprssjava-source-file

    private CDataWriter()
    {

    }

    public static void createHDF5( final String p_filename )
    {

        // Create a new file.
        try
        {
            final hdf5.H5File l_h5file = new hdf5.H5File( p_filename, org.bytedeco.javacpp.hdf5.H5F_ACC_TRUNC );
            l_h5file.close();
        }
        catch ( final Exception l_ex )
        {
            l_ex.printStackTrace();
        }
    }

    public static void test( final String p_name )
    {
        final hdf5.H5File l_file = new hdf5.H5File();
        l_file.openFile( p_name, hdf5.H5F_ACC_RDWR );

        final String l_DATASETNAME = "Results";
        final int l_DIM0 = 100;
        final int l_DIM1 = 20;

        // dataset dimensions
        final long[] l_dims = {l_DIM0, l_DIM1};
        // chunk dimensions
        final long[] l_chunkDims = {20, 20};
        final int[] l_buf = new int[l_DIM0 * l_DIM1];



        // Create the data space for the dataset.
        final hdf5.DataSpace l_dataSpace = new hdf5.DataSpace( 2, l_dims );

        // Modify dataset creation property to enable chunking
        final hdf5.DSetCreatPropList l_plist = new hdf5.DSetCreatPropList();
        l_plist.setChunk( 2, l_chunkDims );

        final hdf5.DataSet l_dataset = new hdf5.DataSet( l_file.asCommonFG().createDataSet( l_DATASETNAME,
                                                                                              new hdf5.DataType( hdf5.PredType.STD_I32BE() ), l_dataSpace, l_plist ) );

        for ( int i = 0; i <  l_DIM0; i++ )
            for ( int j = 0; j < l_DIM1; j++ )
                l_buf[i * l_DIM1 + j] = i + j;

        // Write data to dataset.
        l_dataset.write( new IntPointer( l_buf ), new hdf5.DataType( hdf5.PredType.NATIVE_INT() ) );

        l_dataSpace.close();
        l_dataset.close();
        l_plist.close();
        l_file._close();
    }
}