Recently a question came up with a coworker. What is faster and more robust to do?:
The question came up because the original code was:
It is unknown if the path string contains a trailing slash ("/"). So if a slash isn't concatenated between the path and file name, the created File object would not be a valid representation of the file.
Given that the proper directory separator is not necessarily a '/', the first one is simply wrong. There's a static variable in the File class that contains the right characters; but personally I'd use #2. Don't worry about efficiency at this micro-level -- worry about using efficient algorithms.
I agree with Ernest. #2 is more robust, and that trumps speed per default.
The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - Heraclitus