3

Java でファイルを作成するときに許可される最大パス長を確認するにはどうすればよいですか。私はJava 7を使用しているので、それが役立つ場合はJava NIO2を利用できますが、ファイルシステムで許可されているファイルの最大長を特定し、そのような無効なパスを持つファイルを作成しようとしないようにするにはどうすればよいですか?

特に例外/エラーメッセージはファイルシステムごとに異なる可能性があるため、後で問題に対処しないように作成する前に、パス (部分文字列) を短くしたいと考えています。

WindowsアプリケーションがOSXファイルシステムecteraにアクセスできるため、プラットフォームごとに長さをハードコーディングしたくありません。

ファイルを作成しようとしたときにのみ失敗します。

 try
        {

            Path p = Paths.get("C:/User/Mesh/kkkkkkkkkkkkkkkkkkkkkkkkkkrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk.txt");
            Files.createFile(p);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

与える

java.nio.file.FileSystemException: C:\User\Mesh\kkkkkkkkkkkkkkkkkkkkkkkkkkrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk.txt: The filename, directory name, or volume label syntax is incorrect.

    at sun.nio.fs.WindowsException.translateToIOException(WindowsException.java:86)
    at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:97)
    at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:102)
    at sun.nio.fs.WindowsFileSystemProvider.newByteChannel(WindowsFileSystemProvider.java:229)
    at java.nio.file.Files.newByteChannel(Files.java:315)
    at java.nio.file.Files.createFile(Files.java:586)

Java 6 メソッドとの比較

try
        {
            //File file = new File("C:/User/Mesh/kkkkkkkkkkkkkkkkkkkkkkkkkkrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk.txt");
            Path p = Paths.get("C:/User/Mesh/kkkkkkkkkkkkkkkkkkkkkkkkkkrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk.txt");
            p.toFile().createNewFile();
            //boolean result=file.isFile();
            //System.out.println("Result is:"+result);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

まったく異なるエラーが発生します

java.io.IOException: The filename, directory name, or volume label syntax is incorrect
    at java.io.WinNTFileSystem.createFileExclusively(Native Method)
    at java.io.File.createNewFile(File.java:947)

しかし、ファイルが作成される前に何かをしたいので、本当に無関係です

編集:とにかく255文字が良いデフォルトのように見えますhttp://en.wikipedia.org/wiki/Filename

4

2 に答える 2

0

有効なパス名を作成するために使用できるメソッドがありgetPath、java.nio.file.FileSystemそれ以外の場合は InvalidPathException をスローします。多分それはあなたを助けることができます。

于 2013-01-23T17:04:13.883 に答える
0

これらの行に沿って何かを試してください:

boolean success = true;
File testFile = new File("/a/really/long/name");
try {
    success = testFile.createNewFile();
} catch (IOException ioe) {
    // anyway check the exception, the problem could have been other
    // for example: duplicate name, lack of permissions, etc.
    success = false;
}

if (!success) {
    // error creating file
}
于 2013-01-23T17:02:26.573 に答える