a question of optimization

[Pablo Olmos]

Hi everyone,

Recently a question came up with a coworker. What is faster and more robust to do?:

new File(path+"/"+filename);

or

new File(new File(path),filename);

The question came up because the original code was:

new File(path+filename);

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.

[Ernest Friedman-Hill]

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.

[Ilja Preuss]

I agree with Ernest. #2 is more robust, and that trumps speed per default.