Examples with StreamingStartEventImpl com.vaadin.flow.server.communication.streaming.StreamingStartEventImpl used on opensource projects

Example 1 with StreamingStartEventImpl

use of com.vaadin.flow.server.communication.streaming.StreamingStartEventImpl in project flow by vaadin.

the class StreamReceiverHandler method streamToReceiver.

private final Pair<Boolean, UploadStatus> streamToReceiver(VaadinSession session, final InputStream in, StreamReceiver streamReceiver, String filename, String type, long contentLength) throws UploadException {
    StreamVariable streamVariable = streamReceiver.getStreamVariable();
    if (streamVariable == null) {
        throw new IllegalStateException("StreamVariable for the post not found");
    }
    OutputStream out = null;
    long totalBytes = 0;
    StreamingStartEventImpl startedEvent = new StreamingStartEventImpl(filename, type, contentLength);
    boolean success = false;
    try {
        boolean listenProgress;
        session.lock();
        try {
            streamVariable.streamingStarted(startedEvent);
            out = streamVariable.getOutputStream();
            listenProgress = streamVariable.listenProgress();
        } finally {
            session.unlock();
        }
        // Gets the output target stream
        if (out == null) {
            throw new NoOutputStreamException();
        }
        if (null == in) {
            // No file, for instance non-existent filename in html upload
            throw new NoInputStreamException();
        }
        final byte[] buffer = new byte[MAX_UPLOAD_BUFFER_SIZE];
        long lastStreamingEvent = 0;
        int bytesReadToBuffer;
        do {
            bytesReadToBuffer = in.read(buffer);
            if (bytesReadToBuffer > 0) {
                out.write(buffer, 0, bytesReadToBuffer);
                totalBytes += bytesReadToBuffer;
            }
            if (listenProgress) {
                StreamingProgressEventImpl progressEvent = new StreamingProgressEventImpl(filename, type, contentLength, totalBytes);
                lastStreamingEvent = updateProgress(session, streamVariable, progressEvent, lastStreamingEvent, bytesReadToBuffer);
            }
            if (streamVariable.isInterrupted()) {
                throw new UploadInterruptedException();
            }
        } while (bytesReadToBuffer > 0);
        // upload successful
        out.close();
        StreamVariable.StreamingEndEvent event = new StreamingEndEventImpl(filename, type, totalBytes);
        session.lock();
        try {
            streamVariable.streamingFinished(event);
        } finally {
            session.unlock();
        }
        success = true;
    } catch (UploadInterruptedException | IOException e) {
        // Download is either interrupted by application code or some
        // IOException happens
        onStreamingFailed(session, filename, type, contentLength, streamVariable, out, totalBytes, e);
    // Interrupted exception and IOEXception are not thrown forward:
    // it's enough to fire them via streamVariable
    } catch (final Exception e) {
        onStreamingFailed(session, filename, type, contentLength, streamVariable, out, totalBytes, e);
        // I/O operations).
        throw new UploadException(e);
    }
    return new Pair<>(startedEvent.isDisposed(), success ? UploadStatus.OK : UploadStatus.ERROR);
}