sub addFile {
    my $self = shift;

    my ( $fileName, $newName, $compressionLevel );
    if ( ref( $_[0] ) eq 'HASH' ) {
        $fileName         = $_[0]->{filename};
        $newName          = $_[0]->{zipName};
        $compressionLevel = $_[0]->{compressionLevel};
    }
    else {
        ( $fileName, $newName, $compressionLevel ) = @_;
    }