sub check_mysql_params {
    my( $self ) = @_;

    foreach my $attr ( qw( db username pass ) ) {
        unless( defined $self->$attr ) {
            croak( "Error: attribute '$attr' not set" );
        }
    }
    # eventuell hier noch den connect testen

    return $self;
} # check_mysql_params

sub init {
    my( $self, %params ) = @_;

    # parameter hier setzen
    
    my $driver = $self->driver || 'mysql';
    
    my $checkDriverParamsMethod = "check_${driver}_params";
    if( $self->can( $checkDriverParamsMethod ) {
        $self->$checkDriverParamsMethod;
    }
    else {
        croak "Error: no method '$checkDriverParamsMethod' existing";
    }

} # init