RFR: 8154364: (fs) Files.isSameFile() throws NoSuchFileException with broken symbolic links [v3]

[Alan Bateman]

On Thu, 14 Aug 2025 16:16:17 GMT, Alan Bateman <alanb at openjdk.org> wrote:

>> Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   8154364: Propagate change of previous commit to Windows
>
> src/java.base/unix/classes/sun/nio/fs/UnixFileSystemProvider.java line 430:
> 
>> 428:         // neither exist and comparison of normalized paths is problematic,
>> 429:         // so return false
>> 430:         return false;
> 
> I think you can drop "comparison of normalized paths is problematic" as it begs too many questions for anyone looking at this code.

If lastKey is changed to throw when a last file key cannot be obtained then it would simplify the file access in isSameFile to: 

        UnixFileKey key1;
        try {
            UnixFileAttributes attrs = UnixFileAttributes.getIfExists(file1);
            key1 = (attrs != null) ? attrs.fileKey() : lastFileKey(file1);
        } catch (UnixException e) {
            e.rethrowAsIOException(file1);
            return false;
        }

        UnixFileKey key2;
        try {
            UnixFileAttributes attrs = UnixFileAttributes.getIfExists(file2);
            key2 = (attrs != null) ? attrs.fileKey() : lastFileKey(file2);
        } catch (UnixException e) {
            e.rethrowAsIOException(file2);
            return false;
        }

        return key1.equals(key2);

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26736#discussion_r2284856554