net/src/main/java/com/stanfy/enroscar/rest/request/net/UploadPostConverter.java
private static byte[] generateMultipartBoundary() {
    final Random rand = new Random();
    final int c11 = 11, c30 = 30;
    final byte[] bytes = new byte[rand.nextInt(c11) + c30]; // a random size from 30 to 40
    final byte[] chars = getMultipartChars();
    for (int i = 0; i < bytes.length; i++) {
      bytes[i] = chars[rand.nextInt(chars.length)];
    }
    return bytes;
  }
private static byte[] generateMultipartBoundary() {
    final Random rand = new Random();
    final int c11 = 11, c30 = 30;
    final byte[] bytes = new byte[rand.nextInt(c11) + c30]; // a random size from 30 to 40
    final byte[] chars = getMultipartChars();
    for (int i = 0; i < bytes.length; i++) {
      bytes[i] = chars[rand.nextInt(chars.length)];
    }
    return bytes;
  }
/* From MultipartEntity