Example usage for java.util.stream Collectors summingLong

Introduction

In this page you can find the example usage for java.util.stream Collectors summingLong.

Prototype

public static <T> Collector<T, ?, Long> summingLong(ToLongFunction<? super T> mapper) 

Source Link

Document

Returns a Collector that produces the sum of a long-valued function applied to the input elements.

Usage

From source file:com.ikanow.aleph2.analytics.hadoop.assets.SampleReduceEnrichmentModule.java

@Override
public void onObjectBatch(Stream<Tuple2<Long, IBatchRecord>> batch, Optional<Integer> batch_size,
        Optional<JsonNode> grouping_key) {

    // Just to make it simple 

    // 2 different cases:

    // 1) If I'm a combiner or a single-step reducer, then count the batchs
    //    and emit (key, count)
    // 2) If I'm the second stage of a combine-reduce then sum the counts

    Patterns.match(_stage.get()).andAct().when(s -> s == Stage.map, __ -> {
        batch.forEach(obj -> {/*from   w  w  w  . j  a  v  a2  s. c o  m*/

            final JsonNode new_grouping_key = _key_fields.get().stream().reduce(_mapper.createObjectNode(),
                    (acc, v) -> {
                        final Optional<String> key_field = JsonUtils.getProperty(v, obj._2().getJson())
                                .filter(j -> j.isTextual()).map(j -> j.asText());
                        return key_field.map(kf -> acc.put(v.replaceAll("__+", "_").replace(".", "__"), kf))
                                .orElse(acc);
                    }, (acc1, acc2) -> acc1) // (not possible
            ;

            final ObjectNode to_output = _mapper.createObjectNode().put("count", 1);

            _logger.info("OUTPUT FROM MAP = " + to_output + " key " + new_grouping_key);

            _context.get().emitMutableObject(obj._1(), to_output, Optional.empty(),
                    Optional.of(new_grouping_key));

        });
    }).otherwise(s -> { // combine or reduce

        final long count = batch.map(b -> Optional.ofNullable(b._2().getJson().get("count"))
                .filter(j -> j.isNumber()).map(j -> j.asLong()).orElse(0L))
                .collect(Collectors.summingLong(l -> l));

        final ObjectNode to_output = ((s == Stage.reduce) ? ((ObjectNode) grouping_key.get().deepCopy())
                : _mapper.createObjectNode()).put("count", count);

        _logger.info("OUTPUT FROM COMBINE/REDUCE = " + to_output + " (stage=" + s + " key " + grouping_key);

        _context.get().emitMutableObject(0L, to_output, Optional.empty(),
                (s == Stage.reduce) ? Optional.empty() : grouping_key);
    });
}

---

From source file:org.apache.hadoop.hbase.quotas.FileArchiverNotifierImpl.java

/**
 * Computes the size of each store file in {@code storeFileNames}
 *//*  ww w .ja v  a 2  s. c  om*/
long getSizeOfStoreFiles(TableName tn, Set<StoreFileReference> storeFileNames) {
    return storeFileNames.stream().collect(Collectors.summingLong((sfr) -> getSizeOfStoreFile(tn, sfr)));
}

---

From source file:org.apache.hadoop.hbase.quotas.FileArchiverNotifierImpl.java

/**
 * Computes the size of the store files for a single region.
 *//*w ww . ja  v a  2  s.  com*/
long getSizeOfStoreFile(TableName tn, StoreFileReference storeFileName) {
    String regionName = storeFileName.getRegionName();
    return storeFileName.getFamilyToFilesMapping().entries().stream().collect(
            Collectors.summingLong((e) -> getSizeOfStoreFile(tn, regionName, e.getKey(), e.getValue())));
}

---

From source file:org.apache.hadoop.hbase.quotas.SnapshotQuotaObserverChore.java

/**
 * Sums the snapshot sizes for each namespace.
 *//* w  w  w . j  av a 2s.c  o m*/
Map<String, Long> groupSnapshotSizesByNamespace(Multimap<TableName, SnapshotWithSize> snapshotsWithSize) {
    return snapshotsWithSize.entries().stream().collect(Collectors.groupingBy(
            // Convert TableName into the namespace string
            (e) -> e.getKey().getNamespaceAsString(),
            // Sum the values for namespace
            Collectors.mapping(Map.Entry::getValue, Collectors.summingLong((sws) -> sws.getSize()))));
}

---

From source file:pl.otros.logview.api.gui.LogViewPanelWrapper.java

private void createReadingProgressBar() {
    progressBar = new JProgressBar(0, 100);
    progressBar.setStringPainted(true);/*w w  w. j  a  v  a  2  s.co  m*/
    progressBar.setString("Processed ? of ? [?%]");
    final Timer t = new Timer(500, e -> {
        LOGGER.trace("Updating reading progress");
        final LoadingDetails loadingDetails = logLoader.getLoadingDetails(dataTableModel);
        final List<LogLoadingSession> logLoadingSessions = loadingDetails.getLogLoadingSessions();
        final List<LoadStatistic> statistics = logLoadingSessions.stream().map(logLoader::getLoadStatistic)
                .collect(Collectors.toList());
        final Long position = statistics.stream().collect(Collectors.summingLong(LoadStatistic::getPosition));
        final Long total = statistics.stream().collect(Collectors.summingLong(LoadStatistic::getTotal));
        final float percent = (100f) * ((float) position / total);
        progressBar.setValue((int) percent);
        final String msg = String.format("Processed %s of %s [%.2f%%]",
                FileSize.convertToStringRepresentation(position), FileSize.convertToStringRepresentation(total),
                percent);
        LOGGER.trace("Updating progress bar with message {}", msg);
        progressBar.setString(msg);

        final String tooltip = "<HTML>" + statistics.stream()
                .map(s -> String.format("Processed %s of %s [%.2f%%]  - %s",
                        FileSize.convertToStringRepresentation(s.getPosition()),
                        FileSize.convertToStringRepresentation(s.getTotal()), s.getPercent(),
                        s.getSource().stringForm()))
                .collect(Collectors.joining("<BR/>")) + "</HTML>";
        progressBar.setToolTipText(tooltip);
    });
    t.setRepeats(true);
    t.setInitialDelay(1000);
    t.start();
    timer = Optional.of(t);
}

---