本文整理了Java中java.util.concurrent.ConcurrentHashMap.computeIfAbsent()方法的一些代码示例，展示了ConcurrentHashMap.computeIfAbsent()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。ConcurrentHashMap.computeIfAbsent()方法的具体详情如下：
包路径：java.util.concurrent.ConcurrentHashMap
类名称：ConcurrentHashMap
方法名：computeIfAbsent

ConcurrentHashMap.computeIfAbsent介绍

暂无

代码示例

代码示例来源：origin: neo4j/neo4j

private static Map<String, PropertyGetter> serialization( Class<? extends ObjectRepresentation> type )
{
  Map<String, PropertyGetter> serialization = serializations.computeIfAbsent(
      type, ObjectRepresentation::buildSerialization );
  return serialization;
}

代码示例来源：origin: neo4j/neo4j

ThreadPool getThreadPool( Group group )
{
  return pools.computeIfAbsent( group, poolBuilder );
}

代码示例来源：origin: stanfordnlp/CoreNLP

private synchronized void compileColonPatterns() {
 if (colonsPat == null) {
  colonsPat = new Pattern[colons.length];
  for (int i = 0; i < colons.length; i++) {
   Character colon = colons[i];
   colonsPat[i] = patternMap.computeIfAbsent(WHITE + colon + WHITE, (s) -> Pattern.compile(s));
  }
 }
}

代码示例来源：origin: stanfordnlp/CoreNLP

private synchronized void compileColonsWhitePatterns(String numPat) {
 if (colonsWhitePat == null) {
  colonsWhitePat = new Pattern[colons.length];
  for (int i = 0; i < colons.length; i++) {
   Character colon = colons[i];
   String pattern = "(" + numPat + ")" + WHITEPLUS + colon + WHITEPLUS + "(" + numPat + ")";
   colonsWhitePat[i] = patternMap.computeIfAbsent(pattern, (s) -> Pattern.compile(s));
  }
 }
}

代码示例来源：origin: neo4j/neo4j

private T getLog( String name, Supplier<T> logSupplier )
{
  return logCache.computeIfAbsent( name, s -> logSupplier.get() );
}

代码示例来源：origin: apache/incubator-druid

@VisibleForTesting
public void moveTaskGroupToPendingCompletion(int taskGroupId)
{
 final TaskGroup taskGroup = activelyReadingTaskGroups.remove(taskGroupId);
 if (taskGroup != null) {
  pendingCompletionTaskGroups.computeIfAbsent(taskGroupId, k -> new CopyOnWriteArrayList<>()).add(taskGroup);
 }
}

代码示例来源：origin: stanfordnlp/CoreNLP

private Pattern[] compilePunctuationPatterns() {
 Pattern[] puncsPat = new Pattern[puncs.length];
 for (int i = 0; i < puncs.length; i++) {
  Character punc = puncs[i];
  puncsPat[i] = patternMap.computeIfAbsent(getEscapedPuncPattern(punc), (s) -> Pattern.compile(s));
 }
 return puncsPat;
}

代码示例来源：origin: apache/storm

private LocalizedResource getUserArchive(String user, String key) {
  assert user != null : "All user archives require a user present";
  ConcurrentMap<String, LocalizedResource> keyToResource = userArchives.computeIfAbsent(user, (u) -> new ConcurrentHashMap<>());
  return keyToResource.computeIfAbsent(key, 
    (k) -> new LocalizedResource(key, localBaseDir, true, fsOps, conf, user, metricsRegistry));
}

代码示例来源：origin: apache/storm

/**
 * Go through all executors and time them out if needed.
 * @param topoId the id of the topology to look at.
 * @param taskTimeoutSecs the timeout to know if they are too old.
 */
public void timeoutOldHeartbeats(String topoId, Integer taskTimeoutSecs) {
  Map<List<Integer>, ExecutorCache> topoCache = cache.computeIfAbsent(topoId, MAKE_MAP);
  for (ExecutorCache ec : topoCache.values()) {
    ec.updateTimeout(taskTimeoutSecs);
  }
}

代码示例来源：origin: Netflix/zuul

@Override
public BasicNettyOrigin getOrigin(String name, String vip, String uri, SessionContext ctx) {
  return originMappings.computeIfAbsent(name, n -> createOrigin(name, vip, uri, false, ctx));
}

代码示例来源：origin: Netflix/zuul

public Timing get(String name)
{
  return additionalTimings.computeIfAbsent(name, (newName) -> new Timing(newName));
}

代码示例来源：origin: apache/storm

private LocalizedResource getUserFile(String user, String key) {
  assert user != null : "All user archives require a user present";
  ConcurrentMap<String, LocalizedResource> keyToResource = userFiles.computeIfAbsent(user, (u) -> new ConcurrentHashMap<>());
  return keyToResource.computeIfAbsent(key, 
    (k) -> new LocalizedResource(key, localBaseDir, false, fsOps, conf, user, metricsRegistry));
}

代码示例来源：origin: prestodb/presto

@Override
public <R> R withLease(Function<LookupSourceLease, R> action)
{
  lock.readLock().lock();
  try {
    LookupSource lookupSource = suppliedLookupSources.computeIfAbsent(this, k -> lookupSourceSupplier.getLookupSource());
    LookupSourceLease lease = new SpillAwareLookupSourceLease(lookupSource, spillingInfo);
    return action.apply(lease);
  }
  finally {
    lock.readLock().unlock();
  }
}

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

private boolean offer0(Channel channel, Object partitionKey, long now) {
 ConcurrentLinkedDeque<IdleChannel> partition = partitions.get(partitionKey);
 if (partition == null) {
  partition = partitions.computeIfAbsent(partitionKey, pk -> new ConcurrentLinkedDeque<>());
 }
 return partition.offerFirst(new IdleChannel(channel, now));
}

代码示例来源：origin: ben-manes/caffeine

@Override
public @Nullable V putIfAbsent(K key, V value) {
 requireNonNull(value);
 boolean[] wasAbsent = new boolean[1];
 V val = data.computeIfAbsent(key, k -> {
  writer.write(key, value);
  wasAbsent[0] = true;
  return value;
 });
 return wasAbsent[0] ? null : val;
}

代码示例来源：origin: Netflix/zuul

@Override
public BasicNettyOrigin getOrigin(String name, String vip, String uri, SessionContext ctx) {
  return originMappings.computeIfAbsent(name, n -> createOrigin(name, vip, uri, false, ctx));
}

代码示例来源：origin: Netflix/zuul

public Timing get(String name)
{
  return additionalTimings.computeIfAbsent(name, (newName) -> new Timing(newName));
}

代码示例来源：origin: alibaba/Sentinel

@Override
public long addMachine(MachineInfo machineInfo) {
  AppInfo appInfo = apps.computeIfAbsent(machineInfo.getApp(), app -> new AppInfo(app));
  appInfo.addMachine(machineInfo);
  return 1;
}

代码示例来源：origin: neo4j/neo4j

private void handleSubmission( BoltConnection connection )
{
  activeWorkItems.computeIfAbsent( connection.id(),
      key -> scheduleBatchOrHandleError( connection ).whenCompleteAsync( ( result, error ) -> handleCompletion( connection, result, error ),
          forkJoinPool ) );
}

代码示例来源：origin: apache/storm

@VisibleForTesting
CompletableFuture<Void> requestDownloadBaseTopologyBlobs(PortAndAssignment pna, BlobChangingCallback cb) {
  final String topologyId = pna.getToplogyId();
  final LocallyCachedBlob topoJar = getTopoJar(topologyId, pna.getAssignment().get_owner());
  topoJar.addReference(pna, cb);
  final LocallyCachedBlob topoCode = getTopoCode(topologyId, pna.getAssignment().get_owner());
  topoCode.addReference(pna, cb);
  final LocallyCachedBlob topoConf = getTopoConf(topologyId, pna.getAssignment().get_owner());
  topoConf.addReference(pna, cb);
  return topologyBasicDownloaded.computeIfAbsent(topologyId,
                          (tid) -> downloadOrUpdate(topoJar, topoCode, topoConf));
}