"D:downloadmanagernodewebtorrent.cmd" download "magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel" --select 0 --out "D://nf/"

@Override
public synchronized void start() throws IOException {
    if (mWasDownloadStarted || mWasDownloadFinished) return;

    mExec.getCommand().listIterator().forEachRemaining(s -> {
        System.out.print(s + " ");
    });

    mExec.start();
    setProcessId();

    mWasDownloadStarted = true;
    mWasDownloadStopped = false;
}

private String buildCommand() {
    List <String> command = new ArrayList<>();
    command.add(""" + mManager.mWTLocation + """);
    command.add("download");
    command.add(""" + mManager.mMagnetUrl + """);

    if (mManager.mFileIndex >= 0) {
        command.add("--select " + mManager.mFileIndex);
    }

    if (mManager.mSaveTo != null) {
        command.add("--out "" + mManager.mSaveTo + """);
    }

    mManager.mExec.command(command);

    String cmdStr = "";
    for (String s : command) {
        cmdStr = cmdStr.concat(s + " ");
    }

    return cmdStr.trim();
}