public static MappedByteBuffer mapExistingFile(
        final File location, final String descriptionLabel, final long offset, final long length)
    {
        return mapExistingFile(location, READ_WRITE, descriptionLabel, offset, length);
    }
public static MappedByteBuffer mapExistingFile ( final File location , final String descriptionLabel , final long offset , final long length ) { return mapExistingFile ( location , READ_WRITE , descriptionLabel , offset , length ) ; }
Check that file exists, open file, and return MappedByteBuffer for only region specified as
{@link java.nio.channels.FileChannel.MapMode#READ_WRITE}.
<p>
The file itself will be closed, but the mapping will persist.

@param location         of the file to map
@param descriptionLabel to be associated for an exceptions
@param offset           offset to start mapping at
@param length           length to map region
@return {@link java.nio.MappedByteBuffer} for the file