SQL Developer makes Daily WTF
Mind you, it is a sign of the relative merits of SQL Developer as a tool that the only thing they can find to mock is the code generated by the DDL wizard. As several of the commenters say, most generated code is not the prettiest. Still the code as shown is rather revolting. You wouldn't want to work with anyone who learnt how to program PL/SQL by studying this stuff.
Read the whole thread here.