private int pollCompletedDownloads() {
int tasks = 0;
for (int i = 0; i < completedRequests.size(); i++) {
parserService.submit(new FeedParserTask(completedRequests.poll()));
tasks++;
}
return tasks;
}
/**
* Waits for completed requests. Once the first request has been taken, the method will wait
* WAIT_TIMEOUT ms longer to collect more completed requests.
*
* @return Collected feeds or null if the method has been interrupted during the first waiting
* period.
*/
private List<Feed> collectCompletedRequests() {
List<Feed> results = new LinkedList<Feed>();
DownloadRequester requester = DownloadRequester.getInstance();
int tasks = 0;
try {
DownloadRequest request = completedRequests.take();
parserService.submit(new FeedParserTask(request));
tasks++;
} catch (InterruptedException e) {
return null;
}
tasks += pollCompletedDownloads();
isCollectingRequests = true;
if (requester.isDownloadingFeeds()) {
// wait for completion of more downloads
long startTime = System.currentTimeMillis();
long currentTime = startTime;
while (requester.isDownloadingFeeds() && (currentTime - startTime) < WAIT_TIMEOUT) {
try {
if (BuildConfig.DEBUG)
Log.d(TAG, "Waiting for " + (startTime + WAIT_TIMEOUT - currentTime) + " ms");
sleep(startTime + WAIT_TIMEOUT - currentTime);
} catch (InterruptedException e) {
if (BuildConfig.DEBUG) Log.d(TAG, "interrupted while waiting for more downloads");
tasks += pollCompletedDownloads();
} finally {
currentTime = System.currentTimeMillis();
}
}
tasks += pollCompletedDownloads();
}
isCollectingRequests = false;
for (int i = 0; i < tasks; i++) {
try {
Feed f = parserService.take().get();
if (f != null) {
results.add(f);
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
return results;
}
public void submitCompletedDownload(DownloadRequest request) {
completedRequests.offer(request);
if (isCollectingRequests) {
interrupt();
}
}