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From: Jan Burse <janburse@fastmail.fm>
Newsgroups: comp.lang.java.programmer
Subject: Re: A "current directory" concept for Java...
Date: Sat, 23 Aug 2014 10:31:29 +0200
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Andreas Leitgeb schrieb:
> e.g.: the wrapped Path of curDir originally points to "/tmp", then...
>   - curDir.chDir("foo") would go to "/tmp/foo", then
>   - curDir.chDir("../bar") would go to "/tmp/bar", then
>   - curDir.chDir("/foo") would go to "/foo"

if you use a static variable to hold the current
directory, it will be seen class loader wide.

Means for a standalone application you will
have one current directory, and for web applications
it could happen that each web context has its own
current directory.

public class State {
     private static String curdir;

     public void chDir(String str) {
         curdir = new FIle(curdir,str).getCanonicalPath();
     }

}

The getCanonicalPath() method will usually resolve
../ and ./ parts in the str together with curdir.
But I am not sure how binding the Java contract is.
I find in the comment only saying "typical":

   "A canonical pathname is both absolute and unique.
    The precise definition of canonical form is system-
    dependent.  This method first converts this pathname
    to absolute form if necessary, as if by invoking the
    {@link #getAbsolutePath} method, and then maps it to
    its unique form in a system-dependent way.  This
    typically involves removing redundant names such as
    <tt>"."</tt> and <tt>".."</tt> from the pathname,
    resolving symbolic links (on UNIX platforms), and
    converting drive letters to a standard case (on
    Microsoft Windows platforms)."

Bye