Is there a Java utility which will convert a String path to use the correct File separator char?

Question

I have developed a number of classes which manipulate files in Java. I am working on a Linux box, and have been blissfully typing new File(\"path/to/some/file\");

Answer 1

I create this function to check if a String contain a \ character then convert them to /

public static String toUrlPath(String path) {
  return path.indexOf('\\') < 0 ? path : path.replace('\\', '/');
}

public static String toUrlPath(Path path) {
  return toUrlPath(path.toString());
}

Answer 2

String fileName = Paths.get(fileName).toString();

Works perfectly with Windows at least even with mixed paths, for example

c:\users\username/myproject\myfiles/myfolder

becomes

c:\users\username\myproject\myfiles\myfolder

Sorry haven't check what Linux would make of the above but there again Linux file structure is different so you wouldn't search for such a directory

Answer 3

For anyone trying to do this 7 years later, the apache commons separatorsToSystem method has been moved to the FilenameUtils class:

FilenameUtils.separatorsToSystem(String path)

Answer 4

Apache Commons comes to the rescue (again). The Commons IO method FilenameUtils.separatorsToSystem(String path) will do what you want.

Needless to say, Apache Commons IO will do a lot more besides and is worth looking at.

Answer 5

This is what Apache commons-io does, unrolled into a couple of lines of code:

String separatorsToSystem(String res) {
    if (res==null) return null;
    if (File.separatorChar=='\\') {
        // From Windows to Linux/Mac
        return res.replace('/', File.separatorChar);
    } else {
        // From Linux/Mac to Windows
        return res.replace('\\', File.separatorChar);
    }
}

So if you want to avoid the extra dependency, just use that.

Answer 6

I think there is this hole in Java Paths.

String rootStorePath = Paths.get("c:/projects/mystuff/").toString();

works if you are running it on a system that has the file system you need to use. As pointed out, it used the current OS file system.

I need to work with paths between windows and linux, say to copy a file from one to another. While using "/" every works I guess if you are using all Java commands, but I need to make an sftp call so using / or file.separator etc... does not help me. I cannot use Path() because it converts mine to the default file system I am running on "now".

What Java needs is:
on windows system:

Path posixPath = Paths.get("/home/mystuff", FileSystem.Posix );
stays /home/mystuff/  and does not get converted to \\home\\mystuff

on linux system:
String winPath = Paths.get("c:\home\mystuff", FileSystem.Windows).toString();

stays c:\home\mystuff and does not get converted to /c:/home/mystuff

similar to working with character sets:

URLEncoder.encode( "whatever here", "UTF-8" ).getBytes();

P.S. I also do not want to load a whole apache io jar file to do something simple either. In this case they do not have what I propose anyways.