java - FileOutputStream crashes with "open failed: EISDIR (Is a directory)" error when downloading image

Question

I'm trying to download an iamge from the internet, Here is the code:

try {
                String imgURL = c.imgURL;
                String imgPATH = c.imgPATH;
                URL url = new URL(imgURL);
                URLConnection conexion = url.openConnection();
                conexion.connect();
                int lenghtOfFile = conexion.getContentLength();
                try {
                    File f = new File(imgPATH);
                    f.mkdirs();

                    BufferedInputStream input = new BufferedInputStream(url.openStream());
                    BufferedOutputStream output = new BufferedOutputStream(new FileOutputStream(imgPATH), 8192); // CRASH HERE

                    byte data[] = new byte[8192];
                    long total = 0;
                    int count = 0;
                    int updateUILimiter = 0;
                    while ((count = input.read(data)) != -1) {
                        total += count;

                        if (updateUILimiter == 20)
                            // publishProgress((int) (total * 100 / lenghtOfFile));
                            updateUILimiter = 0;
                        else
                            updateUILimiter++;

                        output.write(data, 0, count);

                        if (isCancelled()) {
                            output.flush();
                            output.close();
                            input.close();
                            return null;
                        }

                    }
                    output.flush();
                    output.close();
                    input.close();
                } catch (Exception e) {
                    c.imgPATH = "";
                    return null;
                }


            } catch (Exception e) {
                c.imgPATH = "";
                return null;
            }

Here is the error message:

/mnt/sdcard/tmp/3.png: open failed: EISDIR (Is a directory)

Why is this?

" /mnt/sdcard/tmp/" exists.

Answer 1

3.png is a directory, because you make it so by calling f.mkdirs();. Try f.getParentFile().mkdirs() instead. From the documentation:

Creates the directory named by this abstract pathname, including any necessary but nonexistent parent directories. Note that if this operation fails it may have succeeded in creating some of the necessary parent directories.

(emphasis mine). In other words, the entire path contained in the File instance f is taken to be a directory name, up to and including the final part (3.png in the example output).