19 September 2013

What means Derived files in Eclipse ?

Solution for Eclipse

So you trying to edit file and Eclipse warns you ...
"This file is derived" Are you sure?

You simply trying edit wrong file.
Really?Well, it depends...

This error  means that you trying edit file, that is created in temporary (usually in target )   directory  by Eclipse during runtime and will be deleted or overwritten ,when application will be restarted/rebuild again. (Hot-swap and  famous Clean button (to solve 98% dirty problems created by Eclipse) will delete this file too.)

2 cases:

If you just trying to modify file to see changes that should be deleted on restart..it is fine. However. it is not good idea to do this way anyway. Specially,when you trying solve annoying problem and you finally fix it,then Eclipse wipe this change.You got mad and forget ,how you fix it... and you are stuck in madness for 5-30 minutes.

If you trying modify original(source) file and edit original file,then it means you open wrong file :).
Just close it and try to find your file in your source files directory/folder.