conditional statements in derby

Question

It looks like derby doesn't support conditional statements [IF]. How do we write

if exists (select 1 from customers where name='somename') 
    update customers ...
else 
    insert into customers ...

in derby? Derby doesn't have 'replace into' of mysql either.

Note: I am using derby as unit-testing replacement for mysql [that is production will use mysql and unit-test will use derby].