@Override
    @SuppressWarnings("unchecked")
    public String map(ResultSet r, int columnNumber, StatementContext ctx) throws SQLException {
        PGobject obj = (PGobject) r.getObject(columnNumber);
        return obj.getValue();
    }
Postgres column mapper for {@code @MacAddr String}.
postgres/src/main/java/org/jdbi/v3/postgres/MacAddrColumnMapper.java