Problem reading subdirectories using FileUtils.listfiles...

Question

I'm trying to get all subdirectories doing this:

   File repositoryDir = new File(_props.getProperty("files.repository.path"));

IOFileFilter filter = new IOFileFilter() {
      public boolean accept(File file) {
          //return file.isDirectory();
       return true;
      }

   @Override
   public boolean accept(File arg0_, String arg1_) {
    // TODO Auto-generated method stub
    return false;
   }
  };

FileUtils.listFiles(repositoryDir,filter,null);

Unfortunately the List returned is empty.

On the other hand if I do this it works:

File[] mainLevelFiles = repositoryDir.listFiles();

Anyone has a clue on what wrong with Apaches FileUtils.listFiles(...)?

Answer 1

The problem is that you have two accept methods, one returning true and one returning false. Remove the one with the extra string, so that it looks like this:

IOFileFilter filter = new AbstractFileFilter() {
  public boolean accept(File file) {
    return file.isDirectory();
  }
};

Alternatively, you could use Apache's DirectoryFileFilter:

 File dir = new File(_props.getProperty("files.repository.path"));
 String[] files = dir.list( DirectoryFileFilter.INSTANCE );
 for ( int i = 0; i < files.length; i++ ) {
     System.out.println(files[i]);
 }