Java ExceptionalFunction0类代码示例

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Void> deleteQueue(final String name, final String password) {
  String passwordHash;
  try {
    passwordHash = PinLaterBackendUtils.getSaltedHash(password);
  } catch (NoSuchAlgorithmException e) {
    return Future.exception(
        new PinLaterException(ErrorCode.UNKNOWN, "Error finding hashing algorithm."));
  }
  if (!passwordHash.equals(configuration.getString("ADMIN_PASSWORD_HASH"))) {
    return Future.exception(
        new PinLaterException(ErrorCode.PASSWORD_INVALID, "Invalid admin password."));
  }

  return futurePool.apply(new ExceptionalFunction0<Void>() {
    @Override
    public Void applyE() throws Throwable {
      deleteQueueImpl(name);
      return null;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Integer> retryFailedJobs(final PinLaterRetryFailedJobsRequest request) {
  // Execute retryFailedJobs query on each shard until we have updated 'limit' number of jobs.
  return futurePool.apply(new ExceptionalFunction0<Integer>() {
    @Override
    public Integer applyE() throws Throwable {
      long currentTimeMillis = System.currentTimeMillis();
      int remainingLimit = request.getLimit();
      List<String> shardNames = getRandomShardShuffle();
      for (final String shardName : shardNames) {
        int numRetried = retryFailedJobsFromShard(
            request.getQueueName(),
            shardName,
            request.getPriority(),
            request.getAttemptsToAllow(),
            request.isSetRunAfterTimestampMillis()
            ? request.getRunAfterTimestampMillis() : currentTimeMillis,
            remainingLimit);
        remainingLimit -= numRetried;
        if (remainingLimit <= 0) {
          break;
        }
      }
      return request.getLimit() - remainingLimit;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Integer> deleteJobs(final PinLaterDeleteJobsRequest request) {
  // Execute deleteJobs query on each shard until we have updated 'limit' number of jobs.
  return futurePool.apply(new ExceptionalFunction0<Integer>() {
    @Override
    public Integer applyE() throws Throwable {
      int remainingLimit = request.getLimit();
      List<String> shardNames = getRandomShardShuffle();
      for (final String shardName : shardNames) {
        int numDeleted = deleteJobsFromShard(
            request.getQueueName(),
            shardName,
            request.getJobState(),
            request.getPriority(),
            request.getBodyRegexToMatch(),
            remainingLimit);
        remainingLimit -= numDeleted;

        if (remainingLimit <= 0) {
          break;
        }
      }
      return request.getLimit() - remainingLimit;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
/**
 * Clean up all the keys in each shard. This method is only for test use.
 */
@VisibleForTesting
public Future<Void> cleanUpAllShards() {
  return futurePool.apply(new ExceptionalFunction0<Void>() {
    @Override
    public Void applyE() throws Throwable {
      for (final ImmutableMap.Entry<String, RedisPools> shard : shardMap.entrySet()) {
        RedisUtils.executeWithConnection(
            shard.getValue().getGeneralRedisPool(),
            new Function<Jedis, Void>() {
              @Override
              public Void apply(Jedis conn) {
                conn.flushAll();
                return null;
              }
            });
      }
      return null;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
/**
 * Remove the job hash from redis. This function is used in test to simulate the case where the
 * job id is still in the queue, while the job hash is evicted by redis LRU.
 */
@VisibleForTesting
public Future<Void> removeJobHash(String jobDescriptor) {
  final PinLaterJobDescriptor jobDesc = new PinLaterJobDescriptor(jobDescriptor);
  return futurePool.apply(new ExceptionalFunction0<Void>() {
    @Override
    public Void applyE() throws Throwable {
      RedisUtils.executeWithConnection(
          shardMap.get(jobDesc.getShardName()).getGeneralRedisPool(),
          new Function<Jedis, Void>() {
            @Override
            public Void apply(Jedis conn) {
              String hashRedisKey = RedisBackendUtils.constructHashRedisKey(
                  jobDesc.getQueueName(), jobDesc.getShardName(), jobDesc.getLocalId());
              conn.del(hashRedisKey);
              return null;
            }
          });
      return null;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
/**
 * Elective stream lock--readers are not required to acquire the lock before using the stream.
 */
synchronized Future<Void> lockStream() {
    if (null == lockAcquireFuture) {
        final Function0<DistributedLock> lockFunction =  new ExceptionalFunction0<DistributedLock>() {
            @Override
            public DistributedLock applyE() throws IOException {
                // Unfortunately this has a blocking call which we should not execute on the
                // ZK completion thread
                BKLogReadHandler.this.readLock = new ZKDistributedLock(
                        lockStateExecutor,
                        lockFactory,
                        readLockPath,
                        conf.getLockTimeoutMilliSeconds(),
                        statsLogger.scope("read_lock"));

                LOG.info("acquiring readlock {} at {}", getLockClientId(), readLockPath);
                return BKLogReadHandler.this.readLock;
            }
        };
        lockAcquireFuture = ensureReadLockPathExist().flatMap(new ExceptionalFunction<Void, Future<Void>>() {
            @Override
            public Future<Void> applyE(Void in) throws Throwable {
                return scheduler.apply(lockFunction).flatMap(new ExceptionalFunction<DistributedLock, Future<Void>>() {
                    @Override
                    public Future<Void> applyE(DistributedLock lock) throws IOException {
                        return acquireLockOnExecutorThread(lock);
                    }
                });
            }
        });
    }
    return lockAcquireFuture;
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
<T> Future<T> processReaderOperation(final Function<BKLogReadHandler, Future<T>> func) {
    initializeFuturePool(false);
    return readerFuturePool.apply(new ExceptionalFunction0<BKLogReadHandler>() {
        @Override
        public BKLogReadHandler applyE() throws Throwable {
            return getReadHandlerForListener(true);
        }
    }).flatMap(new ExceptionalFunction<BKLogReadHandler, Future<T>>() {
        @Override
        public Future<T> applyE(final BKLogReadHandler readHandler) throws Throwable {
            return func.apply(readHandler);
        }
    });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Void> createQueue(final String name) {
  return futurePool.apply(new ExceptionalFunction0<Void>() {
    @Override
    public Void applyE() throws Throwable {
      createQueueImpl(name);
      return null;
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Integer> getJobCount(final PinLaterGetJobCountRequest request) {
  // If no priority is specified, search for jobs of all priorities.
  Range<Integer> priorityRange = request.isSetPriority()
                                 ? Range.closed((int) request.getPriority(),
      (int) request.getPriority()) :
                                 Range.closed(1, numPriorityLevels);
  final ContiguousSet<Integer> priorities =
      ContiguousSet.create(priorityRange, DiscreteDomain.integers());

  // Execute count query on each shard in parallel.
  List<Future<Integer>> futures = Lists.newArrayListWithCapacity(getShards().size());
  for (final String shardName : getShards()) {
    futures.add(futurePool.apply(new ExceptionalFunction0<Integer>() {
      @Override
      public Integer applyE() throws Throwable {
        return getJobCountFromShard(
            request.getQueueName(),
            shardName,
            priorities,
            request.getJobState(),
            request.isCountFutureJobs(),
            request.getBodyRegexToMatch());
      }
    }));
  }

  return Future.collect(futures).map(
      new Function<List<Integer>, Integer>() {
        @Override
        public Integer apply(List<Integer> shardCounts) {
          int totalCount = 0;
          for (Integer shardCount : shardCounts) {
            totalCount += shardCount;
          }
          return totalCount;
        }
      });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<PinLaterDequeueResponse> dequeueJobs(final String source,
                                                   final PinLaterDequeueRequest request) {
  Future<PinLaterDequeueResponse> dequeueFuture;
  try {
    dequeueFuture = dequeueSemaphoreMap.get(request.getQueueName()).acquire().flatMap(
        new Function<Permit, Future<PinLaterDequeueResponse>>() {
          @Override
          public Future<PinLaterDequeueResponse> apply(final Permit permit) {
            return futurePool.apply(new ExceptionalFunction0<PinLaterDequeueResponse>() {
              @Override
              public PinLaterDequeueResponse applyE() throws Throwable {
                return dequeueJobsImpl(source, request, numAutoRetries);
              }
            }).respond(new Function<Try<PinLaterDequeueResponse>, BoxedUnit>() {
              @Override
              public BoxedUnit apply(Try<PinLaterDequeueResponse> responseTry) {
                permit.release();
                return BoxedUnit.UNIT;
              }
            });
          }
        });
  } catch (ExecutionException e) {
    // The dequeueSemaphoreMap's get() can in theory throw an ExecutionException, but we
    // never expect it in practice since our load method is simply new'ing up an AsyncSemaphore.
    dequeueFuture = Future.exception(e);
  }

  // Dequeue requests can contain ack requests as payloads. If so, we execute both in parallel.
  Future<Void> ackFuture = request.isSetJobAckRequest()
                           ? ackDequeuedJobsImpl(request.getJobAckRequest()) : Future.Void();

  return dequeueFuture.join(ackFuture).map(
      new Function<Tuple2<PinLaterDequeueResponse, Void>, PinLaterDequeueResponse>() {
        @Override
        public PinLaterDequeueResponse apply(Tuple2<PinLaterDequeueResponse, Void> tuple) {
          return tuple._1();
        }
      });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Map<String, PinLaterJobInfo>> lookupJobs(final PinLaterLookupJobRequest request) {
  List<Future<Pair<String, PinLaterJobInfo>>> lookupJobFutures =
      Lists.newArrayListWithCapacity(request.getJobDescriptorsSize());
  for (final String jobDescriptor : request.getJobDescriptors()) {
    Future<Pair<String, PinLaterJobInfo>> lookupJobFuture = futurePool.apply(
        new ExceptionalFunction0<Pair<String, PinLaterJobInfo>>() {
          @Override
          public Pair<String, PinLaterJobInfo> applyE() throws Throwable {
            PinLaterJobDescriptor jobDesc = new PinLaterJobDescriptor(jobDescriptor);
            PinLaterJobInfo jobInfo = lookupJobFromShard(
                jobDesc.getQueueName(),
                jobDesc.getShardName(),
                jobDesc.getPriority(),
                jobDesc.getLocalId(),
                request.isIncludeBody());
            return new Pair<String, PinLaterJobInfo>(jobDescriptor, jobInfo);
          }
        });
    lookupJobFutures.add(lookupJobFuture);
  }

  return Future.collect(lookupJobFutures).map(
      new Function<List<Pair<String, PinLaterJobInfo>>, Map<String, PinLaterJobInfo>>() {
        @Override
        public Map<String, PinLaterJobInfo> apply(List<Pair<String, PinLaterJobInfo>> jobPairs) {
          Map<String, PinLaterJobInfo> lookupJobMap = Maps.newHashMap();
          for (Pair<String, PinLaterJobInfo> jobPair : jobPairs) {
            if (jobPair.getSecond() != null) {
              lookupJobMap.put(jobPair.getFirst(), jobPair.getSecond());
            }
          }
          return lookupJobMap;
        }
      });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Void> checkpointJobs(final String source,
                                   final PinLaterCheckpointJobsRequest request) {
  // Partition the requests such that there are roughly <queryParallelism> partitions. Then
  // execute those in parallel. Within each partition, each checkpoint is executed serially.
  List<Future<Void>> futures = Lists.newArrayList();
  if (request.getRequestsSize() > 0) {
    futures.addAll(PinLaterBackendUtils.executePartitioned(
        request.getRequests(),
        queryParallelism,
        new Function<List<PinLaterCheckpointJobRequest>, Future<Void>>() {
          @Override
          public Future<Void> apply(final List<PinLaterCheckpointJobRequest> checkpointRequests) {
            return futurePool.apply(new ExceptionalFunction0<Void>() {
              @Override
              public Void applyE() throws Throwable {
                for (PinLaterCheckpointJobRequest checkpointRequest : checkpointRequests) {
                  checkpointSingleJob(source, request.getQueueName(), checkpointRequest,
                      numAutoRetries);
                }
                return null;
              }
            });
          }
        }));
  }
  return Future.collect(futures).voided();
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<Set<String>> getQueueNames() {
  return futurePool.apply(new ExceptionalFunction0<Set<String>>() {
    @Override
    public Set<String> applyE() throws Throwable {
      return getQueueNamesImpl();
    }
  });
}
 

import com.twitter.util.ExceptionalFunction0; //导入依赖的package包/类
public Future<PinLaterScanJobsResponse> scanJobs(final PinLaterScanJobsRequest request) {
  // Validate continuation token. CONTINUATION_START is the only supported token right now.
  if (!request.getContinuation().equals(Constants.CONTINUATION_START)) {
    return Future.exception(new PinLaterException(ErrorCode.CONTINUATION_INVALID,
        "CONTINUATION_START is the only continuation token supported right now."));
  }

  // If no priority is specified, search for jobs of all priorities.
  Range<Integer> priorityRange = request.isSetPriority()
                                 ? Range.closed((int) request.getPriority(),
      (int) request.getPriority()) :
                                 Range.closed(1, numPriorityLevels);
  final ContiguousSet<Integer> priorities =
      ContiguousSet.create(priorityRange, DiscreteDomain.integers());

  // Execute scanJobs query on each shard in parallel.
  List<Future<List<PinLaterJobInfo>>> futures =
      Lists.newArrayListWithCapacity(getShards().size());
  for (final String shardName : getShards()) {
    futures.add(futurePool.apply(new ExceptionalFunction0<List<PinLaterJobInfo>>() {
      @Override
      public List<PinLaterJobInfo> applyE() throws Throwable {
        return scanJobsFromShard(
            request.getQueueName(),
            shardName,
            priorities,
            request.getJobState(),
            request.isScanFutureJobs(),
            request.getContinuation(),
            request.getLimit(),
            request.getBodyRegexToMatch());
      }
    }));
  }

  // Perform a merge, and then truncate at the requested limit.
  return Future.collect(futures).map(
      new Function<List<List<PinLaterJobInfo>>, PinLaterScanJobsResponse>() {
        @Override
        public PinLaterScanJobsResponse apply(List<List<PinLaterJobInfo>> shardLists) {
          // First grab all of the lists of job info and perform a merge on them.
          List<PinLaterJobInfo> mergedList = PinLaterBackendUtils.mergeIntoList(
              shardLists,
              PinLaterBackendUtils.JobInfoComparator.getInstance(),
              request.getLimit());

          // If we were to support continuation we would need to create and set the token here.
          // Right now, we just leave it as the default: CONTINUATION_END.
          return new PinLaterScanJobsResponse(mergedList);
        }
      });
}