57

Rewrote question with more info

I have some code that creates a Path object using relative paths, like this: Paths.get("..", "folder").resolve("filename"). Later, I want to get the path string "..\folder\filename" from it (I'm on windows, so backslashes). When I run this code using manual compile or from Eclipse, this works fine.

However, when I run it using Maven, it doesn't work any more. The toString() method returns [.., folder, filename] instead of an actual path string. Using path.normalize() doesn't help. Using path.toFile().getPath() does return what I'm looking for, but I feel there should be a solution using just the nio.path API.

Jorn
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    That doesn't seem right. Both `Paths.get("path/to/file").toString()` and `Paths.get("path", "to", "file").toString()` both return `"path/to/file"` for me. – cambecc Jul 09 '13 at 15:38
  • Same is true of `Paths.get("path/to").resolve("file").toString()`, which returns `"path/to/file"`. – cambecc Jul 09 '13 at 15:39
  • I may be wrong but for me both returns the same string !!! – AllTooSir Jul 09 '13 at 15:39
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    What result do you see for `Paths.get("path", "to", "file").getClass().getName()`? Perhaps you're picking up a wonky FileSystem implementation. – cambecc Jul 09 '13 at 15:43
  • The difference might be that I'm starting with going up one path (relative to working directory): `Paths.get("..", "path/to", "file")`. I didn't think it would be relevant to the question, but apparently it is. – Jorn Jul 09 '13 at 15:45
  • Again, this doesn't result in anything surprising: `Paths.get("..", "path/to", "file").toString()` returns `"../path/to/file"`. I'm using JDK 1.7.0_21 – cambecc Jul 09 '13 at 15:49

2 Answers2

67

Use:

Paths.get(...).normalize().toString()

Another solution woul be:

Paths.get(...).toAbsolutePath().toString()

However, you get strange results: Paths.get("/tmp", "foo").toString() returns /tmp/foo here. What is your filesystem?

fge
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7

To complete the the fge's answer, I would add some info:

  1. normalize() simply removes redundant pieces of strings in your path, like . or ..; it does not operate at the OS level or gives you an absolute path from a relative path
  2. toAbsolutePath() on the contrary gives you what the name says, the absolute path of the Path object. But...
  3. toRealPath() resolves also soft and hard links (yes they exists also on Windows, so win user, you're not immune). So it gives to you, as the name says, the real path.

So what's the best? It depends, but personally I use toRealPath() the 99% of the cases.

As pointed out by Roberto Bonvallet, since toRealPath() throws an exception if the file does not already exist because, for example, you want to create it. In this case I prefer toAbsolutePath().

Source: Official javadoc

Marco Sulla
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