/**
* Execute the task.
*
* @return true if it works, false otherwise.
*/
@Override
public Boolean call() {
final long start = System.nanoTime();
CompletionStatus result = CompletionStatus.FAILED;
try {
Log.d(LOG_TAG, "Download Task started for download id = " + downloadId);
failureMessage = MSG_OKAY;
downloadErrorCode = DownloadError.NO_ERROR.getValue();
if (!ensureFolderExists(destination)) {
finish(
CompletionStatus.FAILED,
failureMessage,
cumulativeBytesRead,
totalBytes,
autoRestart,
downloadErrorCode);
return false;
}
if (null != downloadTag && 0L < downloadOffset) {
if (!ensurePartialFilePresent(destination, downloadOffset)) {
// if we don't have the partial file any more, we have to start again
downloadOffset = 0L;
}
}
result = readFromUri(destination);
finish(
result, failureMessage, cumulativeBytesRead, totalBytes, autoRestart, downloadErrorCode);
return CompletionStatus.SUCCEEDED == result;
} finally {
// Make sure we release wifi lock (if any)
networkStatusProvider.releaseWifiLock(downloadId);
final long duration = System.nanoTime() - start;
Log.d(
LOG_TAG,
String.format(
"Download result(%s) for download task with uri(%s) took %.3f seconds.",
result.name(), uri, (double) duration / 1000000000));
}
}
/** Poller main loop */
@Override
public void run() {
for (; ; ) {
CompletionStatus info;
try {
info = GetQueuedCompletionStatus(port);
} catch (WindowsException x) {
// this should not happen
x.printStackTrace();
return;
}
// wakeup
if (info.completionKey() == WAKEUP_COMPLETION_KEY) {
boolean shutdown = processRequests();
if (shutdown) {
return;
}
continue;
}
// map completionKey to get WatchKey
WindowsWatchKey key = ck2key.get((int) info.completionKey());
if (key == null) {
// We get here when a registration is changed. In that case
// the directory is closed which causes an event with the
// old completion key.
continue;
}
boolean criticalError = false;
int errorCode = info.error();
int messageSize = info.bytesTransferred();
if (errorCode == ERROR_NOTIFY_ENUM_DIR) {
// buffer overflow
key.signalEvent(StandardWatchEventKinds.OVERFLOW, null);
} else if (errorCode != 0 && errorCode != ERROR_MORE_DATA) {
// ReadDirectoryChangesW failed
criticalError = true;
} else {
// ERROR_MORE_DATA is a warning about incomplete
// data transfer over TCP/UDP stack. For the case
// [messageSize] is zero in the most of cases.
if (messageSize > 0) {
// process non-empty events.
processEvents(key, messageSize);
} else if (errorCode == 0) {
// insufficient buffer size
// not described, but can happen.
key.signalEvent(StandardWatchEventKinds.OVERFLOW, null);
}
// start read for next batch of changes
try {
ReadDirectoryChangesW(
key.handle(),
key.buffer().address(),
CHANGES_BUFFER_SIZE,
key.watchSubtree(),
ALL_FILE_NOTIFY_EVENTS,
key.countAddress(),
key.overlappedAddress());
} catch (WindowsException x) {
// no choice but to cancel key
criticalError = true;
}
}
if (criticalError) {
implCancelKey(key);
key.signal();
}
}
}
