Getting "java.nio.file.AccessDeniedException" when trying to write to a folder

Question

For some reason I keep getting java.nio.file.AccessDeniedException every time I try to write to a folder on my computer using a java webapp on Tomcat. This folder has permissions set to full control for everyone on my computer (Windows). Does anybody know why I get this exception?

Here's my code:

public void saveDocument(String name, String siteID, byte doc[]) {
    try {
        Path path = Paths.get(rootDirectory + siteID);
        if (Files.exists(path)) {
            System.out.println("Exists: " + path.toString());
            Files.write(path, doc);
        } else {
            System.out.println("DOesn't exist");
            throw new Exception("Directory for Site with ID " + siteID + "doesn't exist");
        }
    } catch (FileSystemException e) {
        System.out.println("Exception: " + e);
        e.printStackTrace();
    } catch (IOException e ) {
        System.out.println("Exception: " + e);
        e.printStackTrace();
    } catch (Exception e) {
        System.out.println("Exception: " + e);
        e.printStackTrace();
    }

And here is the error:

Exception: java.nio.file.AccessDeniedException: C:\safesite_documents\site1 java.nio.file.AccessDeniedException: C:\safesite_documents\site1 at sun.nio.fs.WindowsException.translateToIOException(WindowsException.java:83) 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:230) at java.nio.file.spi.FileSystemProvider.newOutputStream(FileSystemProvider.java:430) at java.nio.file.Files.newOutputStream(Files.java:172) at java.nio.file.Files.write(Files.java:3092)

Possible reason why: See my post on supersuser about how I can't uncheck 'Read Only' for any of my folders on windows 7. Even though all the folders aren't read only to anything but java.

Answer 1

Ok it turns out I was doing something stupid. I hadn't appended the new file name to the path.

I had

rootDirectory = "C:\\safesite_documents"

but it should have been

rootDirectory = "C:\\safesite_documents\\newFile.jpg" 

Sorry it was a stupid mistake as always.

Answer 2

Getting java.nio.file.AccessDeniedException when trying to write to a folder

Unobviously, Comodo antivirus has an "Auto-Containment" setting that can cause this exact error as well. (e.g. the user can write to a location, but the java.exe and javaw.exe processes cannot).

In this edge-case scenario, adding an exception for the process and/or folder should help.

Temporarily disabling the antivirus feature will help understand if Comodo AV is the culprit.

I post this not because I use or prefer Comodo, but because it's a tremendously unobvious symptom to an otherwise functioning Java application and can cost many hours of troubleshooting file permissions that are sane and correct, but being blocked by a 3rd-party application.

Answer 3

I was getting the same error when trying to copy a file. Closing a channel associated with the target file solved the problem.

Path destFile = Paths.get("dest file");
SeekableByteChannel destFileChannel = Files.newByteChannel(destFile);
//...
destFileChannel.close();  //removing this will throw java.nio.file.AccessDeniedException:
Files.copy(Paths.get("source file"), destFile);