ava.io.IOException：open failed：ENOENT（没有这样的文件或目录）

Question

我的项目是一名下载管理员。当我想提供下载链接时，它给了我错误。 我认为我的承诺是找不到下载的链接，但我找不到我的错误。 这是我的代码：

@Override
    public void run() {
        try {
            URL url = new URL(mission.url);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            mission.length = conn.getContentLength();

            if (mission.length <= 0) {
                mission.errCode = DownloadMission.ERROR_SERVER_UNSUPPORTED;
                //mission.notifyError(DownloadMission.ERROR_SERVER_UNSUPPORTED);
                return;
            }

            // Open again
            conn = (HttpURLConnection) url.openConnection();
            conn.setRequestProperty("Range", "bytes=" + (mission.length - 10) + "-" + mission.length);

            if (conn.getResponseCode() != 206) {
                // Fallback to single thread if no partial content support
                mission.fallback = true;

                if (DEBUG) {
                    Log.d(TAG, "falling back");
                }
            }

            if (DEBUG) {
                Log.d(TAG, "response = " + conn.getResponseCode());
            }

            mission.blocks = mission.length / BLOCK_SIZE;

            if (mission.threadCount > mission.blocks) {
                mission.threadCount = (int) mission.blocks;
            }

            if (mission.threadCount <= 0) {
                mission.threadCount = 1;
            }

            if (mission.blocks * BLOCK_SIZE < mission.length) {
                mission.blocks++;
            }


            new File(mission.location).mkdirs();
            new File(mission.location + "/" + mission.name).createNewFile();
            RandomAccessFile af = new RandomAccessFile(mission.location + "/" + mission.name, "rw");
            af.setLength(mission.length);
            af.close();

            mission.start();
        } catch (Exception e) {
            // TODO Notify
            throw new RuntimeException(e);
        }
    }

这是获取网址的地方。 有什么建议吗？