本文整理了Java中java.util.stream.LongStream.sum()方法的一些代码示例，展示了LongStream.sum()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。LongStream.sum()方法的具体详情如下：
包路径：java.util.stream.LongStream
类名称：LongStream
方法名：sum

LongStream.sum介绍

[英]Returns the sum of elements in this stream. This is a special case of a reduction and is equivalent to:

return reduce(0, Long::sum);

This is a terminal operation.
[中]返回此流中元素的总和。这是reduction的一个特例，相当于：

return reduce(0, Long::sum);

这是一个terminal operation。

代码示例

代码示例来源：origin: google/guava

/**
 * Returns the sum of all values in this map.
 *
 * <p>This method is not atomic: the sum may or may not include other concurrent operations.
 */
public long sum() {
 return map.values().stream().mapToLong(Long::longValue).sum();
}

代码示例来源：origin: prestodb/presto

public long getPhysicalWrittenDataSize()
{
  return drivers.stream()
      .mapToLong(DriverContext::getPphysicalWrittenDataSize)
      .sum();
}

代码示例来源：origin: prestodb/presto

public long getPphysicalWrittenDataSize()
{
  return operatorContexts.stream()
      .mapToLong(OperatorContext::getPhysicalWrittenDataSize)
      .sum();
}

代码示例来源：origin: prestodb/presto

@Override
public long getJoinPositionCount()
{
  return Arrays.stream(lookupSources)
      .mapToLong(LookupSource::getJoinPositionCount)
      .sum();
}

代码示例来源：origin: prestodb/presto

@Override
public long getSizeInBytes()
{
  return INSTANCE_SIZE + channels.stream()
      .flatMap(List::stream)
      .mapToLong(Block::getRetainedSizeInBytes)
      .sum();
}

代码示例来源：origin: prestodb/presto

@Override
public long getInMemorySizeInBytes()
{
  return Arrays.stream(lookupSources).mapToLong(LookupSource::getInMemorySizeInBytes).sum();
}

代码示例来源：origin: neo4j/neo4j

@Override
public long maxCount()
{
  return partitionReaders.stream().mapToLong( LucenePartitionAllDocumentsReader::maxCount ).sum();
}

代码示例来源：origin: prestodb/presto

/**
 * Returns the sum of all values in this map.
 *
 * <p>This method is not atomic: the sum may or may not include other concurrent operations.
 */
public long sum() {
 return map.values().stream().mapToLong(Long::longValue).sum();
}

代码示例来源：origin: prestodb/presto

public StripeStatistics(List<ColumnStatistics> columnStatistics)
{
  this.columnStatistics = ImmutableList.copyOf(requireNonNull(columnStatistics, "columnStatistics is null"));
  this.retainedSizeInBytes = INSTANCE_SIZE + columnStatistics.stream().mapToLong(ColumnStatistics::getRetainedSizeInBytes).sum();
}

代码示例来源：origin: prestodb/presto

public long getUserMemoryReservation()
{
  return stages.values().stream()
      .mapToLong(SqlStageExecution::getUserMemoryReservation)
      .sum();
}

代码示例来源：origin: prestodb/presto

public void compact()
{
  checkState(!finished, "NestedLoopJoinPagesBuilder is finished");
  pages.stream()
      .forEach(Page::compact);
  estimatedSize = pages.stream()
      .mapToLong(Page::getRetainedSizeInBytes)
      .sum();
}

代码示例来源：origin: prestodb/presto

public long getTotalMemoryReservation()
{
  return stages.values().stream()
      .mapToLong(SqlStageExecution::getTotalMemoryReservation)
      .sum();
}

代码示例来源：origin: prestodb/presto

@JsonProperty
public long getWrittenPositions()
{
  return operatorSummaries.stream()
      .filter(stats -> stats.getOperatorType().equals(TableWriterOperator.class.getSimpleName()))
      .mapToLong(OperatorStats::getInputPositions)
      .sum();
}

代码示例来源：origin: prestodb/presto

private synchronized void addPages(Collection<SerializedPageReference> pages)
{
  pages.forEach(SerializedPageReference::addReference);
  this.pages.addAll(pages);
  long rowCount = pages.stream().mapToLong(SerializedPageReference::getPositionCount).sum();
  rowsAdded.addAndGet(rowCount);
  pagesAdded.addAndGet(pages.size());
  long bytesAdded = pages.stream().mapToLong(SerializedPageReference::getRetainedSizeInBytes).sum();
  bufferedBytes.addAndGet(bytesAdded);
}

代码示例来源：origin: prestodb/presto

public long getTotalPartitionsCount(String keyspace, String table, Optional<Long> sessionSplitsPerNode)
{
  if (sessionSplitsPerNode.isPresent()) {
    return sessionSplitsPerNode.get();
  }
  else if (configSplitsPerNode.isPresent()) {
    return configSplitsPerNode.get();
  }
  List<SizeEstimate> estimates = session.getSizeEstimates(keyspace, table);
  return estimates.stream()
      .mapToLong(SizeEstimate::getPartitionsCount)
      .sum();
}

代码示例来源：origin: AsyncHttpClient/async-http-client

/**
 * @return A long representing the number of active connections in the connection pool.
 */
public long getTotalActiveConnectionCount() {
 return statsPerHost
     .values()
     .stream()
     .mapToLong(HostStats::getHostActiveConnectionCount)
     .sum();
}

代码示例来源：origin: RichardWarburton/java-8-lambdas-exercises

public long countFeature(ToLongFunction<Album> function) {
  return albums.stream()
      .mapToLong(function)
      .sum();
}

代码示例来源：origin: AsyncHttpClient/async-http-client

/**
 * @return The sum of {@link #getTotalActiveConnectionCount()} and {@link #getTotalIdleConnectionCount()},
 * a long representing the total number of connections in the connection pool.
 */
public long getTotalConnectionCount() {
 return statsPerHost
     .values()
     .stream()
     .mapToLong(HostStats::getHostConnectionCount)
     .sum();
}

代码示例来源：origin: prestodb/presto

public Optional<IndexInfo> build()
  {
    List<Integer> partitions = partitionsSizes.build();
    if (partitions.size() == 0) {
      return Optional.empty();
    }
    double avgSize = partitions.stream().mapToLong(Integer::longValue).average().getAsDouble();
    double squaredDifferences = partitions.stream().mapToDouble(size -> Math.pow(size - avgSize, 2)).sum();
    checkState(partitions.stream().mapToLong(Integer::longValue).sum() == rowsNumber, "Total number of rows in index does not match number of rows in partitions within that index");
    return Optional.of(new IndexInfo(rowsNumber, sizeInBytes, squaredDifferences, partitions.size()));
  }
}

代码示例来源：origin: AsyncHttpClient/async-http-client

/**
 * @return A long representing the number of idle connections in the connection pool.
 */
public long getTotalIdleConnectionCount() {
 return statsPerHost
     .values()
     .stream()
     .mapToLong(HostStats::getHostIdleConnectionCount)
     .sum();
}