How to change source file name for class?

[Asperamanca]

How do I change the source file name a class is related with, without generating new code?
Or how do I specify a filename when synchronizing with code?

[Asperamanca]

Solved

Back up the source files, generate code using the new file name, then overwrite the generated code using the backup, and synchronize with code.

I wonder what would be so hard to just add the source file name of a class in the properties dialog  
There's even a file tab right there!