Question

I have two tasks, one for download and another for unzip;

public class DownloadUtil {

    public static void downloadHtml(MainViewController controller, String dns, int port, String offlineUUID, String filePath, Map<String, String> cookies) throws IOException {

        String urlHtml = "http://" + dns + ":" + port + Constants.TARGET_SERVICE_DOWNLOADFILES + offlineUUID;

        System.out.println(urlHtml);

        Executors.newSingleThreadExecutor().execute(new DownloaderTask(controller, urlHtml, filePath, cookies));
    }

and

public class UnzipUtil {

    public static void unZipIt(String zipFile, String outputFolder) {

        Executors.newSingleThreadExecutor().execute(new UnzipTask(zipFile, outputFolder));
    }
}

and I call them in my code this way:

DownloadUtil.downloadHtml(this, dns, port, uuid, filePathHtmlDownload, cookies);
UnzipUtil.unZipIt(filePathHtmlDownload, outputFolder);

But the problem is that the Unzip method is calling before the download method finish, how can I do to unZipIt wait for downloadHtml method?

Answer 1

Pass the same SingleThreadExecutor to both methods. Your tasks are then done sequentially by the Executor.

Executor e = Executors.newSingleThreadExecutor();
DownloadUtil.downloadHtml(e, this, dns, port, uuid, filePathHtmlDownload, cookies);
UnzipUtil.unZipIt(e, filePathHtmlDownload, outputFolder);

And your methods now look like:

public class DownloadUtil {

public static void downloadHtml(Executor e, MainViewController controller, String dns, int port, String offlineUUID, String filePath, Map<String, String> cookies) throws IOException {

    ...

    e.execute(new DownloaderTask(controller, urlHtml, filePath, cookies));
}