Resolve a path name with .. parent directory specifiers ("dot dot") without resolving symlinks

Question

Given a path like /a/./b/c/../d, I would like to remove all the "current directory" indicators (i.e., period) and "parent directory" indicators (i.e., ..), giving a/b/d.

I could use File.getCanonicalPath(), but that also resolves symlinks, which I don't want.

Any simple way? That is, simpler than writing a tokenizer and handling it all myself.

Bonus points if you can tell me what the right name for '.' and '..' are in this context.

Answer 1

Guava also has this as Files.simplifyPath(String). Your best bet, though, (if you can use JDK7) is to represent your path as a Path and use Path.normalize() to get the normalized version.

Answer 2

You can use FilenameUtils.normalize() in the Apache Commons IO library - see javadoc here.

"Dot" (.) is the current directory and "dot dot" (..) is the parent directory - read up on unix directories.

Answer 3

Have also a look at this question (Java 7 or newer): Java: how to normalize paths with nio Path?

The solution is great, but it is not portable (it will not work on Windows machines).