IMHO you should set up personal rules for creating temporary files and try to strictly adhere to this rule.
My personal rule is that temp*.* or tmp*.* or *.tmp or *.temp (i.e. files that start or end with "temp" or "tmp") are temporary files which can be erased with no hesitation. If I created one of these today, I'll remember what it is, otherwise it can be purged without bothering to look at it and try and decide what is was being used for.
This rule allows me to have a CreateTemp.java file and know that I should keep it.