Java Code Examples for java.util.concurrent.atomic.AtomicInteger#decrementAndGet()

@Override
public CompletableFuture writeAsync(int opId, Object... args) {
  Integer result;
  AtomicInteger counter = counters.get(testName);
  boolean shouldModify = (boolean) args[0];
  switch (opId) {
    case 1:
      result = shouldModify ? counter.incrementAndGet() : counter.get();
      break;
    case 2:
      result = shouldModify ? counter.decrementAndGet() : counter.get();
      break;
    default:
      throw new SamzaException("Invalid opId: " + opId);
  }
  return CompletableFuture.completedFuture(result);
}
 

private static <T> Consumer<T> provideObserverResult(final rx.Observer<? super T> observer,
                                                     final AtomicInteger counter,
                                                     final AtomicBoolean errorTrigger,
                                                     final boolean failOnError) {
  return result -> {
    if (result.isSuccess()) {
      observer.onNext(result.getValue());
      if (counter.decrementAndGet() == 0) {
        observer.onCompleted();
      }
    } else {
      if (failOnError) {
        if (errorTrigger.compareAndSet(false, true)) {
          observer.onError(result.getError());
        }
        counter.set(0);
      } else {
        if (counter.decrementAndGet() == 0) {
          observer.onCompleted();
        }
      }
    }
  };
}
 

private void pollQueue(final Subscriber<? super T> child,
                       AtomicLong requested,

                       AtomicInteger bufferedCount,
                       AtomicBoolean onCompleteReceived,
                       AtomicInteger completionEmitted,
                       AtomicInteger wip) {
    do {
        drainIfPossible(child, requested, bufferedCount, onCompleteReceived, completionEmitted);
        long c = wip.decrementAndGet();
        if (c > 1) {
            /*
             * Set down to 1 and then iterate again.
             * we lower it to 1 otherwise it could have grown very large while in the last poll loop
             * and then we can end up looping all those times again here before existing even once we've drained
             */
            wip.set(1);
            // we now loop again, and if anything tries scheduling again after this it will increment and cause us to loop again after
        }
    } while (wip.get() > 0);
}
 

@Override
public <T, R> RFuture<Collection<R>> readAllAsync(Collection<R> results, Codec codec, RedisCommand<T> command, Object... params) {
    RPromise<Collection<R>> mainPromise = createPromise();
    Collection<MasterSlaveEntry> nodes = connectionManager.getEntrySet();
    AtomicInteger counter = new AtomicInteger(nodes.size());
    BiConsumer<Object, Throwable> listener = new BiConsumer<Object, Throwable>() {
        @Override
        public void accept(Object result, Throwable u) {
            if (u != null && !(u instanceof RedisRedirectException)) {
                mainPromise.tryFailure(u);
                return;
            }
            
            if (result instanceof Collection) {
                synchronized (results) {
                    results.addAll((Collection) result);
                }
            } else {
                synchronized (results) {
                    results.add((R) result);
                }
            }
            
            if (counter.decrementAndGet() == 0
                    && !mainPromise.isDone()) {
                mainPromise.trySuccess(results);
            }
        }
    };

    for (MasterSlaveEntry entry : nodes) {
        RPromise<R> promise = new RedissonPromise<R>();
        promise.onComplete(listener);
        async(true, new NodeSource(entry), codec, command, params, promise, true);
    }
    return mainPromise;
}
 

@Override
public void prefetchAll(final Iterable<? extends K> _keys, final CacheOperationCompletionListener l) {
  final CacheOperationCompletionListener _listener= l != null ? l : DUMMY_LOAD_COMPLETED_LISTENER;
  if (loader == null) {
    _listener.onCompleted();
    return;
  }
  Set<K> _keysToLoad = checkAllPresent(_keys);
  final AtomicInteger _count = new AtomicInteger(2);
  try {
    for (K k : _keysToLoad) {
      final K key = k;
      Runnable r = new RunWithCatch(this) {
        @Override
        public void action() {
          try {
            getEntryInternal(key);
          } finally {
            if (_count.decrementAndGet() == 0) {
              _listener.onCompleted();
            }
          }
        }
      };
      try {
        getPrefetchExecutor().execute(r);
        _count.incrementAndGet();
      } catch (RejectedExecutionException ignore) { }
    }
  } finally {
    if (_count.addAndGet(-2) == 0) {
      _listener.onCompleted();
    }
  }
}
 

@Override
public CompletableFuture<Void> removeOwnedNamespaceBundleAsync(NamespaceBundle namespaceBundle) {
    NamespaceName namespace = namespaceBundle.getNamespaceObject();
    AtomicInteger bundlesCount = ownedBundlesCountPerNamespace.get(namespace);
    if (bundlesCount == null || bundlesCount.decrementAndGet() <= 0) {
        CompletableFuture<SystemTopicClient.Reader> readerCompletableFuture = readerCaches.remove(namespace);
        if (readerCompletableFuture != null) {
            readerCompletableFuture.thenAccept(SystemTopicClient.Reader::closeAsync);
            ownedBundlesCountPerNamespace.remove(namespace);
            policyCacheInitMap.remove(namespace);
            policiesCache.entrySet().removeIf(entry -> entry.getKey().getNamespaceObject().equals(namespace));
        }
    }
    return CompletableFuture.completedFuture(null);
}
 

protected void handle(RPromise<Void> mainPromise, AtomicInteger slots, RFuture<?> future) {
    if (future.isSuccess()) {
        if (slots.decrementAndGet() == 0) {
            mainPromise.trySuccess(null);
        }
    } else {
        mainPromise.tryFailure(future.cause());
    }
}
 

@NonNull
private static <T, R> List<T> checkLevel(R targetValue,
                                         List<T> previousLevel,
                                         BiFunction<R, List<T>, Boolean> predicate,
                                         int level,
                                         int permutationIndex,
                                         AtomicInteger maxIterations) {
    if (previousLevel.size() == 1) {
        return new ArrayList<>();
    }
    for (int i = permutationIndex; i < previousLevel.size(); i++) {
        if (maxIterations.get() <= 0) {
            return new ArrayList<>();
        }
        List<T> newList = new ArrayList<>(previousLevel);
        newList.remove(i);
        if (level == 0) {
            maxIterations.decrementAndGet();
            // Check all permutations on this level
            if (predicate.apply(targetValue, newList)) {
                return newList;
            }
        } else {
            // Test next level
            var result = checkLevel(targetValue, newList, predicate, level - 1, i, maxIterations);
            if (!result.isEmpty()) {
                return result;
            }
        }
    }
    return new ArrayList<>();
}
 

@Test
public void immediateTaskIsExecuted() throws Exception {
	Scheduler serviceRB = Schedulers.newSingle("rbWork");
	Scheduler.Worker r = serviceRB.createWorker();

	long start = System.currentTimeMillis();
	AtomicInteger latch = new AtomicInteger(1);
	Consumer<String> c =  ev -> {
		latch.decrementAndGet();
		try {
			System.out.println("ev: "+ev);
			Thread.sleep(1000);
		}
		catch(InterruptedException ie){
			throw Exceptions.propagate(ie);
		}
	};
	r.schedule(() -> c.accept("Hello World!"));

	Thread.sleep(1200);
	long end = System.currentTimeMillis();

	serviceRB.dispose();

	Assert.assertTrue("Event missed", latch.intValue() == 0);
	Assert.assertTrue("Timeout too long", (end - start) >= 1000);
}
 

void fillHomeBuckets(Collection<KBucketEntry> entries) {
	if(node.getNumEntriesInRoutingTable() == 0 && entries.isEmpty()) {
		bootstrapping.set(BootstrapState.NONE);
		return;
	}
	
	bootstrapping.set(BootstrapState.BOOTSTRAP);
	
	final AtomicInteger taskCount = new AtomicInteger();
	
	TaskListener bootstrapListener = t -> {
		int count = taskCount.decrementAndGet();
		if(count == 0) {
			bootstrapping.set(BootstrapState.NONE); ;
			lastBootstrap = System.currentTimeMillis();
		}
			
		// fill the remaining buckets once all bootstrap operations finished
		if (count == 0 && running && node.getNumEntriesInRoutingTable() > DHTConstants.USE_BT_ROUTER_IF_LESS_THAN_X_PEERS) {
			node.fillBuckets();
		}
	};
	
	for(RPCServer srv : serverManager.getAllServers()) {
		findNode(srv.getDerivedID(), true, true, srv, t -> {
			taskCount.incrementAndGet();
			t.setInfo("Bootstrap: lookup for self");
			t.injectCandidates(entries);
			t.addListener(bootstrapListener);
		});
	}
	
	if(taskCount.get() == 0)
		bootstrapping.set(BootstrapState.NONE);
	
}
 

@Override
public void execute() {
	
	checkNoCycleInExtensions();
	
	/*
	 * 1. Init independant frequency
	 */
	logger.debug("Init INDEPENDANT_FREQUENCY for all terms");
	terminology
		.terms()
		.forEach(t-> t.setProperty(
				TermProperty.INDEPENDANT_FREQUENCY, 
				t.getFrequency()));
	
	
	/*
	 * 2. Compute depths
	 */
	logger.debug("Computing DEPTH property for all terms");
	final AtomicInteger depth = setDepths();
	logger.debug("Depth of terminology is {}", depth.intValue());
	
	
	/*
	 * 3. Score INDEPENDANT_FREQUENCY
	 */
	logger.debug("Computing INDEPENDANT_FREQUENCY by  for all terms");
	do {
		terminology
			.terms()
			.filter(t -> t.isPropertySet(TermProperty.DEPTH))
			.filter(t -> t.getDepth() == depth.intValue())
			.forEach(t -> {
				final int frequency = t.getIndependantFrequency();
				getBases(t)
					.forEach(base -> {
						int baseFrequency = base.getIndependantFrequency();
						baseFrequency -= frequency;
						base.setProperty(TermProperty.INDEPENDANT_FREQUENCY, baseFrequency);
					});
			});
			depth.decrementAndGet();
	} while(depth.intValue() > 0);
	
	
	/*
	 * 4. Score INDEPENDANCE
	 */
	logger.debug("Computing INDEPENDANCE for all terms");
	terminology.terms()
		.forEach(t -> {
			double iFreq = (double)t.getIndependantFrequency();
			int freq = t.getFrequency();
			t.setProperty(TermProperty.INDEPENDANCE, 
					iFreq / freq);
		});

}
 

@Override
public ResultInfo updateProgress(String taskId, String srcCid, String dstCid, int pieceNum,
    PeerPieceStatus pieceStatus) {
    String msg = null;
    if (StringUtils.isBlank(srcCid)) {
        msg = new StringBuilder().append("src cid is empty for taskId:").append(taskId).toString();
        logger.error(msg);
        return new ResultInfo(ResultCode.UNKNOWN_ERROR, msg, null);
    }

    BitSet pieceBitSet = getBitSetByCid(taskId, srcCid);
    if (pieceBitSet == null) {
        msg = new StringBuilder().append("peer progress not found for taskId:").append(taskId).append(",cid:")
            .append(srcCid).toString();
        logger.error(msg);
        return new ResultInfo(ResultCode.UNKNOWN_ERROR, msg, null);
    }
    if (PeerPieceStatus.SUCCESS.equals(pieceStatus)) {
        ResultInfo tmpResult = processPieceSuc(taskId, srcCid, pieceNum);
        if (!tmpResult.successCode()) {
            return tmpResult;
        }
    }
    if (PeerPieceStatus.SEMISUC.equals(pieceStatus)) {
        pieceStatus = PeerPieceStatus.SUCCESS;
    }

    synchronized (pieceBitSet) {
        if (pieceBitSet.get(pieceNum * 8 + pieceStatus.getStatus())) {
            return new ResultInfo(ResultCode.SUCCESS);
        }

        boolean result = updateProgressBitSet(srcCid, dstCid, pieceBitSet, pieceNum, pieceStatus);
        if (!result) {
            return new ResultInfo(ResultCode.SUCCESS);
        }
        if (PeerPieceStatus.SUCCESS.equals(pieceStatus)) {
            processPeerSucInfo(srcCid, dstCid);
        } else if (PeerPieceStatus.FAIL.equals(pieceStatus)) {
            processPeerFailInfo(srcCid, dstCid);
        }
    }
    if (StringUtils.isNotBlank(dstCid)) {
        AtomicInteger load = progressRepo.getProducerLoad(dstCid);
        if (load != null) {
            int loadValue = load.decrementAndGet();
            if (loadValue < 0) {
                logger.warn("client load maybe illegal,taskId:{},cid:{},pieceNum:{},load:{}",
                    taskId, dstCid, pieceNum, loadValue);
                load.incrementAndGet();
            }
        }
    }
    return new ResultInfo(ResultCode.SUCCESS);
}
 

<T> void indexLogs(Logger logger, Marker marker, int numberOfProducers, Supplier<T> logSupplier) throws InterruptedException {

        final AtomicInteger sleepTime = new AtomicInteger(INITIAL_SLEEP_PER_THREAD);
        CountDownLatch latch = new CountDownLatch(numberOfProducers);

        int numberOfLogsToDeliver = numberOfLogs.get();
        AtomicInteger totalCounter = new AtomicInteger();
        for (int thIndex = 0; thIndex < numberOfProducers; thIndex++) {
            new Thread(() -> {

                for (;numberOfLogs.decrementAndGet() >= 0; totalCounter.incrementAndGet()) {
                    logger.info(marker, logSupplier.get());
                    localCounter.incrementAndGet();
                    try {
                        sleep(sleepTime.get());
                    } catch (InterruptedException e) {
                        interrupted();
                    }

                }
                latch.countDown();
            }).start();
        }

        final int limitPerSec = getInt("smokeTest.limitPerSec", 10000);
        while (latch.getCount() != 0) {
            sleep(1000);
            int count = localCounter.getAndSet(0);
            if (count > limitPerSec && sleepTime.get() != 1) {
                sleepTime.incrementAndGet();
            } else if (sleepTime.get() > 1) {
                sleepTime.decrementAndGet();
            }

            String stats = String.format(
                    "Sleep millis per thread: %d, Current throughput: %d; Progress: %d/%d",
                    sleepTime.get(),
                    count,
                    totalCounter.get(),
                    numberOfLogsToDeliver);

            System.out.println(stats);
        }

        sleep(MILLIS_BEFORE_SHUTDOWN);

        System.out.println("Shutting down");
        LogManager.shutdown();

        sleep(MILLIS_AFTER_SHUTDOWN);

    }
 

GlobDirectoryStream(final DirectoryStream<Path> directoryStream, final Path globPath,
    final DirectoryStream.Filter<Path> filter, final AtomicInteger openCounter) throws IOException {
  this.openCounter = openCounter;
  this.directoryStream = directoryStream;
  final Iterator<Path> dirIterator = directoryStream.iterator();
  iterator = new Iterator<Path>() {
    Iterator<Path> it = Collections.emptyIterator();

    @Override
    public boolean hasNext() {
      try {
        while (!it.hasNext() && dirIterator.hasNext()) {
          if (childDirectoryStream != null) {
            childDirectoryStream.close();
            childDirectoryStream = null;
            openCounter.decrementAndGet();
          }
          Path basePath = dirIterator.next();
          if (Files.isDirectory(basePath)) {
            childDirectoryStream = new GlobDirectoryStream(basePath, globPath, filter, openCounter);
            openCounter.incrementAndGet();
            it = childDirectoryStream.iterator();
          }
        }
        boolean hasNext = it.hasNext();
        if (!hasNext) {
          if (childDirectoryStream != null) {
            childDirectoryStream.close();
            childDirectoryStream = null;
            openCounter.decrementAndGet();
          }
        }
        return hasNext;
      } catch (IOException ex) {
        throw  new RuntimeException(ex);
      }
    }

    @Override
    public Path next() {
      Utils.checkState(hasNext(), "Iterator does not have more elements");
      return it.next();
    }

    @Override
    public void remove() {
      throw new UnsupportedOperationException();
    }
  };
}
 

public void testClusterStatePublishingWithFaultyNodeBeforeCommit() throws InterruptedException {
    VotingConfiguration singleNodeConfig = new VotingConfiguration(Sets.newHashSet(n1.getId()));
    initializeCluster(singleNodeConfig);

    AssertingAckListener ackListener = new AssertingAckListener(nodes.size());
    DiscoveryNodes discoveryNodes = DiscoveryNodes.builder().add(n1).add(n2).add(n3).localNodeId(n1.getId()).build();

    AtomicInteger remainingActions = new AtomicInteger(4); // number of publish actions + initial faulty nodes injection
    int injectFaultAt = randomInt(remainingActions.get() - 1);
    logger.info("Injecting fault at: {}", injectFaultAt);

    Set<DiscoveryNode> initialFaultyNodes = remainingActions.decrementAndGet() == injectFaultAt ?
        Collections.singleton(n2) : Collections.emptySet();
    MockPublication publication = node1.publish(CoordinationStateTests.clusterState(1L, 2L,
        discoveryNodes, singleNodeConfig, singleNodeConfig, 42L), ackListener, initialFaultyNodes);

    publication.pendingPublications.entrySet().stream().collect(shuffle()).forEach(e -> {
        if (remainingActions.decrementAndGet() == injectFaultAt) {
            publication.onFaultyNode(n2);
        }
        if (e.getKey().equals(n2) == false || randomBoolean()) {
            PublishResponse publishResponse = nodeResolver.apply(e.getKey()).coordinationState.handlePublishRequest(
                publication.publishRequest);
            e.getValue().onResponse(new PublishWithJoinResponse(publishResponse, Optional.empty()));
        }
    });

    publication.pendingCommits.entrySet().stream().collect(shuffle()).forEach(e -> {
        nodeResolver.apply(e.getKey()).coordinationState.handleCommit(publication.applyCommit);
        e.getValue().onResponse(TransportResponse.Empty.INSTANCE);
    });

    assertTrue(publication.completed);
    assertTrue(publication.committed);

    publication.onFaultyNode(randomFrom(n1, n3)); // has no influence

    List<Tuple<DiscoveryNode, Throwable>> errors = ackListener.awaitErrors(0L, TimeUnit.SECONDS);
    assertThat(errors.size(), equalTo(1));
    assertThat(errors.get(0).v1(), equalTo(n2));
    assertThat(errors.get(0).v2().getMessage(), containsString("faulty node"));
}
 

/**
 * Converts a collection of {@link ListenableFuture}'s into a single {@link ListenableFuture} 
 * where the result will be the first result provided from the collection.
 * <p>
 * If {@code ignoreErrors} is {@code false} the returned future will complete as soon as the 
 * first future completes, if it completes in error then the error would be returned.  If 
 * {@code ignoreErrors} is {@code true} then the returned future will complete once a result is 
 * provided, or once all futures have completed in error.  If all futures did complete in error 
 * then the last error state will be specified to the resulting {@link ListenableFuture}.  This 
 * minor bookkeeping to ignore errors does incur a slight overhead.
 * <p>
 * It is expected that the first result is the only result desired, once it is found this will 
 * attempt to cancel all remaining futures.  If you may want other results which were in 
 * progress, then specifying {@code interruptOnCancel} as {@code false} will mean that any 
 * futures which started can complete.  You can then inspect the collection for done futures 
 * which might have a result.  If there is no concern for other results, then you likely will 
 * want to interrupt started futures.
 * 
 * @since 5.38
 * @param <T> type of result provided in the returned future
 * @param c Collection of futures to monitor for result
 * @param ignoreErrors {@code false} to communicate the first completed future state, even if in error
 * @param interruptOnCancel {@code true} to send a interrupt on any running futures after we have a result
 * @return A future which will be provided the first result from any in the provided {@link Collection}
 */
public static <T> ListenableFuture<T> makeFirstResultFuture(Collection<? extends ListenableFuture<? extends T>> c, 
                                                            boolean ignoreErrors, boolean interruptOnCancel) {
  SettableListenableFuture<T> result = new SettableListenableFuture<>(false);
  FutureCallback<T> callback;
  if (ignoreErrors) {
    AtomicInteger errorsRemaining = new AtomicInteger(c.size());
    callback = new FutureCallback<T>() {
      @Override
      public void handleResult(T t) {
        if (result.setResult(t)) {
          FutureUtils.cancelIncompleteFutures(c, interruptOnCancel);
        }
      }

      @Override
      public void handleFailure(Throwable t) {
        if (errorsRemaining.decrementAndGet() == 0) {
          // ignore failures till we reach the last failure
          result.setFailure(t);
        }
      }
    };
  } else {
    callback = new FutureCallback<T>() {
      @Override
      public void handleResult(T t) {
        if (result.setResult(t)) {
          FutureUtils.cancelIncompleteFutures(c, interruptOnCancel);
        }
      }

      @Override
      public void handleFailure(Throwable t) {
        if (result.setFailure(t)) {
          FutureUtils.cancelIncompleteFutures(c, interruptOnCancel);
        }
      }
    };
  }
  
  c.forEach((lf) -> lf.callback(callback));

  return result;
}
 

@Override
public int bulkInsert(Uri uri, ContentValues[] values) {
    final int callingUser = UserHandle.getCallingUserId();
    if (LOCAL_LOGV) Slog.v(TAG, "bulkInsert() for user " + callingUser);
    SqlArguments args = new SqlArguments(uri);
    if (TABLE_FAVORITES.equals(args.table)) {
        return 0;
    }
    checkWritePermissions(args);
    SettingsCache cache = cacheForTable(callingUser, args.table);

    final AtomicInteger mutationCount;
    synchronized (this) {
        mutationCount = sKnownMutationsInFlight.get(callingUser);
    }
    if (mutationCount != null) {
        mutationCount.incrementAndGet();
    }
    DatabaseHelper dbH = getOrEstablishDatabase(
            TABLE_GLOBAL.equals(args.table) ? UserHandle.USER_OWNER : callingUser);
    SQLiteDatabase db = dbH.getWritableDatabase();
    db.beginTransaction();
    try {
        int numValues = values.length;
        for (int i = 0; i < numValues; i++) {
            checkUserRestrictions(values[i].getAsString(Settings.Secure.NAME), callingUser);
            if (db.insert(args.table, null, values[i]) < 0) return 0;
            SettingsCache.populate(cache, values[i]);
            if (LOCAL_LOGV) Log.v(TAG, args.table + " <- " + values[i]);
        }
        db.setTransactionSuccessful();
    } finally {
        db.endTransaction();
        if (mutationCount != null) {
            mutationCount.decrementAndGet();
        }
    }

    sendNotify(uri, callingUser);
    return values.length;
}
 

private String tryGetCid(Set<String> blackSet) {
    AtomicInteger load;
    String cid = null;
    String tmpCid;
    int times = pieceContainer.size();
    boolean needOffer;
    while (times-- > 0) {
        needOffer = true;
        tmpCid = pieceContainer.peek();

        if (tmpCid == null) {
            pieceHitLogger.info("peek element from empty queue");
            break;
        }
        if (progressRepo.getServiceDownInfo(tmpCid)) {
            needOffer = false;
        } else {
            AtomicInteger errorCount = progressRepo
                .getServiceErrorInfo(tmpCid);
            if (errorCount != null
                && errorCount.get() >= Constants.ELIMINATION_LIMIT) {
                needOffer = false;
            } else {
                if (blackSet == null || !blackSet.contains(tmpCid)) {
                    load = progressRepo.getProducerLoad(tmpCid);
                    if (load != null) {
                        if (load.incrementAndGet() <= Constants.PEER_UP_LIMIT) {
                            cid = tmpCid;
                            break;
                        } else {
                            load.decrementAndGet();
                        }
                    } else {
                        needOffer = false;
                    }
                }
            }
        }
        synchronized (pieceContainer) {
            if (StringUtils.equals(pieceContainer.peek(), tmpCid)) {
                if (pieceContainer.remove(tmpCid) && needOffer) {
                    pieceContainer.offer(tmpCid);
                }
            }
        }

    }

    return cid;
}
 

/**
 * Verify that "write" operations for a single table are serialized,
 * but different tables can be executed in parallel.
 */
@Test
public void testConcurrentWriteOps() throws Exception {
  final TestTableProcSet procSet = new TestTableProcSet(queue);

  final int NUM_ITEMS = 10;
  final int NUM_TABLES = 4;
  final AtomicInteger opsCount = new AtomicInteger(0);
  for (int i = 0; i < NUM_TABLES; ++i) {
    TableName tableName = TableName.valueOf(String.format("testtb-%04d", i));
    for (int j = 1; j < NUM_ITEMS; ++j) {
      procSet.addBack(new TestTableProcedure(i * 100 + j, tableName,
        TableProcedureInterface.TableOperationType.EDIT));
      opsCount.incrementAndGet();
    }
  }
  assertEquals(opsCount.get(), queue.size());

  final Thread[] threads = new Thread[NUM_TABLES * 2];
  final HashSet<TableName> concurrentTables = new HashSet<>();
  final ArrayList<String> failures = new ArrayList<>();
  final AtomicInteger concurrentCount = new AtomicInteger(0);
  for (int i = 0; i < threads.length; ++i) {
    threads[i] = new Thread() {
      @Override
      public void run() {
        while (opsCount.get() > 0) {
          try {
            Procedure proc = procSet.acquire();
            if (proc == null) {
              queue.signalAll();
              if (opsCount.get() > 0) {
                continue;
              }
              break;
            }

            TableName tableId = procSet.getTableName(proc);
            synchronized (concurrentTables) {
              assertTrue("unexpected concurrency on " + tableId, concurrentTables.add(tableId));
            }
            assertTrue(opsCount.decrementAndGet() >= 0);
            try {
              long procId = proc.getProcId();
              int concurrent = concurrentCount.incrementAndGet();
              assertTrue("inc-concurrent="+ concurrent +" 1 <= concurrent <= "+ NUM_TABLES,
                concurrent >= 1 && concurrent <= NUM_TABLES);
              LOG.debug("[S] tableId="+ tableId +" procId="+ procId +" concurrent="+ concurrent);
              Thread.sleep(2000);
              concurrent = concurrentCount.decrementAndGet();
              LOG.debug("[E] tableId="+ tableId +" procId="+ procId +" concurrent="+ concurrent);
              assertTrue("dec-concurrent=" + concurrent, concurrent < NUM_TABLES);
            } finally {
              synchronized (concurrentTables) {
                assertTrue(concurrentTables.remove(tableId));
              }
              procSet.release(proc);
            }
          } catch (Throwable e) {
            LOG.error("Failed " + e.getMessage(), e);
            synchronized (failures) {
              failures.add(e.getMessage());
            }
          } finally {
            queue.signalAll();
          }
        }
      }
    };
    threads[i].start();
  }
  for (int i = 0; i < threads.length; ++i) {
    threads[i].join();
  }
  assertTrue(failures.toString(), failures.isEmpty());
  assertEquals(0, opsCount.get());
  assertEquals(0, queue.size());

  for (int i = 1; i <= NUM_TABLES; ++i) {
    final TableName table = TableName.valueOf(String.format("testtb-%04d", i));
    final TestTableProcedure dummyProc = new TestTableProcedure(100, table,
      TableProcedureInterface.TableOperationType.DELETE);
    assertTrue("queue should be deleted, table=" + table,
      queue.markTableAsDeleted(table, dummyProc));
  }
}
 

public static void trans(int from, int to) {
  AtomicInteger fromCount = counts.get(from);
  AtomicInteger toCount = counts.get(to);
  toCount.incrementAndGet();
  fromCount.decrementAndGet();
}