SQL & PL/SQL

I have some urls in a table like so

http://test.com/abc/ghgh.html

http://test.com/bcd/

http://test.com/fff/default.aspx

http:// test2.com/a

I want to select everything before the last /

but if the last / is after the .com then just get it how it is.

so above should result in

http://test.com/abc

http://test.com/bcd

http://test.com/fff

http:// test2.com/a

create table testing2 (

url varchar2(50)

);

insert into testing2 values ('http://test.com/abc/ghgh.html');

insert into testing2 values ('http://test.com/bcd/');

insert into testing2 values ('http://test.com/fff/default.aspx');

insert into testing2 values ('http:// test2.com/a');