Reading a directory returns null when deployed on the apache tomcat 7.0 server

Question

I'm trying to read a folder on a network and retrieve a list of txt files. When testing it locally in Eclipse, it works fine, however whenever I deploy it on the Apache Tomcat 7 server it returns null.

It doesn't seem to be an access right problem since the server has access to the folder I'm trying to browse. I'm not sure what is going wrong there, is it a setting on the server I need to change or something else?

private List<File> readDirectory() {
    File test = new File(envMap.get(database));
    List<File> files = new ArrayList<File>();
    try {
        files = FileListing.getFileListing(test);
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    List<File> txtFiles = new ArrayList<File>();
    if (files != null) {
        for (File file : files) {
            if (file.isFile() && file.getName().endsWith(".txt")) {
                txtFiles.add(file);
            }
        }
    }
    return txtFiles;
}

I used this http://www.javapractices.com/topic/TopicAction.do?Id=68 for FileListing.getFileListing

After double checking it turns out that I'm getting a FileNotFoundException: Directory does not exist. The directory does exists and the server has access rights on it, so I'm not really sure of what to do.

Yes. The List files is null after that. It works fine in Eclipse, so I don't think there's a problem with the function. — noisegrrrl, Sep 04 '13 at 12:34
Then you will have to show us how that is implemented. Also there is no point initially initializing it to `= new ArrayList();` since you're reassigning it. — Sotirios Delimanolis, Sep 04 '13 at 12:35
Any OS differences between your local Eclipse setup and Tomcat server machine? — Mauren, Sep 04 '13 at 12:35
I used this: http://www.javapractices.com/topic/TopicAction.do?Id=68 — noisegrrrl, Sep 04 '13 at 12:36
No exceptions are being thrown, And yes, there is eclipse is on a windows 7 while the server is running 2003 server. — noisegrrrl, Sep 04 '13 at 12:37
Yes. There are. EDIT: The files are on another network folder actually, not on the server that's running the application. — noisegrrrl, Sep 04 '13 at 12:39

score 0 · Answer 1 · answered Sep 04 '13 at 12:40

0

files cannot be null. Your code uses

static private List<File> getFileListingNoSort(File aStartingDir) throws FileNotFoundException {
    List<File> result = new ArrayList<File>();
    File[] filesAndDirs = aStartingDir.listFiles(); // may return null
    List<File> filesDirs = Arrays.asList(filesAndDirs); // would throw NPE
    for(File file : filesDirs) {
        result.add(file); 
        if (!file.isFile()) {
            //must be a directory               
            List<File> deeperList = getFileListingNoSort(file);
            result.addAll(deeperList);
        }
    }
    return result;
}

Are you sure you are showing us the right code?

answered Sep 04 '13 at 12:40

Sotirios Delimanolis

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@Emualynk I will delete my answer, but you should definitely debug the code and check where the `null` originates. – Sotirios Delimanolis Sep 04 '13 at 12:46
Is there a way I can access the java console when it's running on the server (and not eclipse)? – noisegrrrl Sep 04 '13 at 13:01
@Emualynk Yeah, take a look at http://stackoverflow.com/questions/975271/remote-debugging-a-java-application – Sotirios Delimanolis Sep 04 '13 at 13:24
After checking it actually does throw a FileNotFoundException this one in particular: `"Directory does not exist: " + aDirectory` – noisegrrrl Sep 04 '13 at 13:48

score 0 · Accepted Answer · answered Sep 05 '13 at 12:33

Found out what the problem was, turns out that by default Apache is running under a Local System Account that has no network access. Changing that to another account with network access solved the problem.

Source: http://blog.mattwoodward.com/2010/08/accessing-network-drive-from-apache-and.html

Reading a directory returns null when deployed on the apache tomcat 7.0 server

2 Answers2