Although you able to decompile your Java class file using Jad, the original source code that accidentally deleted still make life easier.
But it is often that after you file accidentally deleted, then only you start regret why you do not install undelete utility at the first place.
Don’t worry, it is not too late to download and run the Restoration. This is a simple standalone (no installation required) file undelete utility. It able to recover the file deleted before the first time you run it!
This simple utility able to recover most but not all file. So it is still worth to install a fullfledge undelete utility after all.