SimpleProblemCollector problems = new SimpleProblemCollector();
validator.validate( model, problems );
assertEquals( 0, problems.messages.size() );
Repository repo = new Repository();
prof.addRepository( repo );
problems = new SimpleProblemCollector();
validator.validate( model, problems );
assertEquals( 2, problems.messages.size() );
repo.setUrl( "http://xxx.xxx.com" );