//old
try {
            in = getBaseContext().getContentResolver().openInputStream(imageUri);
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NullPointerException e) {
            e.printStackTrace();
            return;
        }
        byte[] buf = new byte[0];
        try {
            assert in != null;
            buf = new byte[in.available()];
            while (in.read(buf) != -1) ;
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NullPointerException e) {
            e.printStackTrace();
            return;
        }

//new
try (InputStream in = getBaseContext().getContentResolver().openInputStream(imageUri)) {
            if (in != null) {
                buf = new byte[in.available()];
                while (in.read(buf) != -1) ;
            }
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NullPointerException e) {
            e.printStackTrace();
            return;
        }