Examples with AProducerQueueIterator de.invesdwin.util.collections.iterable.concurrent.AProducerQueueIterator used on opensource projects

Example 1 with AProducerQueueIterator

use of de.invesdwin.util.collections.iterable.concurrent.AProducerQueueIterator in project invesdwin-context-persistence by subes.

the class ATimeSeriesUpdater method doUpdate.

private void doUpdate() {
    final Pair<FDate, List<V>> pair = lookupTable.prepareForUpdate();
    final FDate updateFrom = pair.getFirst();
    final List<V> lastValues = pair.getSecond();
    Assertions.checkNotNull(lastValues);
    ICloseableIterable<? extends V> source = getSource(updateFrom);
    if (updateFrom != null) {
        // ensure we add no duplicate values
        source = new ASkippingIterable<V>(source) {

            @Override
            protected boolean skip(final V element) {
                return extractTime(element).isBefore(updateFrom);
            }
        };
    }
    final FlatteningIterable<? extends V> flatteningSources = new FlatteningIterable<>(lastValues, source);
    try (ICloseableIterator<? extends V> elements = flatteningSources.iterator()) {
        final ICloseableIterator<UpdateProgress> batchWriterProducer = new ICloseableIterator<UpdateProgress>() {

            @Override
            public boolean hasNext() {
                return elements.hasNext();
            }

            @Override
            public UpdateProgress next() {
                final UpdateProgress progress = new UpdateProgress();
                while (elements.hasNext()) {
                    final V element = elements.next();
                    if (progress.onElement(element)) {
                        return progress;
                    }
                }
                return progress;
            }

            @Override
            public void close() {
                elements.close();
            }
        };
        // do IO in a different thread than batch filling
        try (ACloseableIterator<UpdateProgress> batchProducer = new AProducerQueueIterator<UpdateProgress>(getClass().getSimpleName() + "_batchProducer_" + table.hashKeyToString(key), BATCH_QUEUE_SIZE) {

            @Override
            protected ICloseableIterator<ATimeSeriesUpdater<K, V>.UpdateProgress> newProducer() {
                return batchWriterProducer;
            }
        }) {
            final AtomicInteger flushIndex = new AtomicInteger();
            try (ACloseableIterator<UpdateProgress> parallelConsumer = new AParallelChunkConsumerIterator<UpdateProgress, UpdateProgress>(getClass().getSimpleName() + "_batchConsumer_" + table.hashKeyToString(key), batchProducer, BATCH_WRITER_THREADS) {

                @Override
                protected UpdateProgress doWork(final UpdateProgress request) {
                    request.write(flushIndex.incrementAndGet());
                    return request;
                }
            }) {
                while (parallelConsumer.hasNext()) {
                    final UpdateProgress progress = parallelConsumer.next();
                    count += progress.getCount();
                    if (minTime == null) {
                        minTime = progress.getMinTime();
                    }
                    maxTime = progress.getMaxTime();
                }
            }
        }
    }
}