File manipulation vies with AWT for being the part of Java where
it’s hardest to write truly cross-platform, robust code. Until
Java 2, Sun really didn’t pay a lot of attention to differences
between filesystems on different platforms. The situation is getting
better, however. The
java.io.File class does work
much more reliably across Windows and Unix in Java 2 and has hooks to
allow it to work more naturally on other platforms as well. Of
course, Java 1.1 is still the primary delivery platform for most Java
applications that work with files. To help you achieve greater
serenity and overall cross-platform nirvana, I’ve summarized
some basic rules from this chapter to help you write file
manipulation code that’s robust across a multitude of
Never, never, never hardcode pathnames in your application.
Ask the user to name your files. If you must provide a name for a file, try to make it fit in an 8.3 DOS filename with only pure ASCII characters.
Do not assume the file separator is “/” (or anything
Do not parse pathnames to find directories. Use the methods of the
java.io.File class instead.
Do not use
renameTo() for anything except renaming
a file. In particular, do not use it to move a file.
Try to avoid moving and copying files from within Java programs if at all possible.
Do not use . to refer to the current directory. Use
System.getProperty ("user.dir") instead.
Do not use .. to refer ...