private boolean charge()

in src/main/java/build/buildfarm/cas/cfc/CASFileCache.java [2450:2522]
70 lines of code
15 McCabe index (conditional complexity)

  private boolean charge(String key, long blobSizeInBytes, AtomicBoolean requiresDischarge)
      throws IOException, InterruptedException {
    boolean interrupted = false;
    Iterable<ListenableFuture<Digest>> expiredDigestsFutures;
    synchronized (this) {
      if (referenceIfExists(key)) {
        return false;
      }
      sizeInBytes += blobSizeInBytes;
      requiresDischarge.set(true);

      ImmutableList.Builder<ListenableFuture<Digest>> builder = ImmutableList.builder();
      try {
        while (!interrupted && sizeInBytes > maxSizeInBytes) {
          ListenableFuture<Entry> expiredFuture = expireEntry(blobSizeInBytes, expireService);
          interrupted = Thread.interrupted();
          if (expiredFuture != null) {
            builder.add(
                transformAsync(
                    expiredFuture,
                    (expiredEntry) -> {
                      String expiredKey = expiredEntry.key;
                      try {
                        Files.delete(getPath(expiredKey));
                      } catch (NoSuchFileException eNoEnt) {
                        logger.log(
                            Level.SEVERE,
                            format(
                                "CASFileCache::putImpl: expired key %s did not exist to delete",
                                expiredKey));
                      }
                      FileEntryKey fileEntryKey = parseFileEntryKey(expiredKey, expiredEntry.size);
                      if (fileEntryKey == null) {
                        logger.log(
                            Level.SEVERE, format("error parsing expired key %s", expiredKey));
                      } else if (storage.containsKey(
                          getKey(fileEntryKey.getDigest(), !fileEntryKey.getIsExecutable()))) {
                        return immediateFuture(null);
                      }
                      expiredKeyCounter.inc();
                      logger.log(Level.INFO, format("expired key %s", expiredKey));
                      return immediateFuture(fileEntryKey.getDigest());
                    },
                    expireService));
          }
        }
      } catch (InterruptedException e) {
        // clear interrupted flag
        Thread.interrupted();
        interrupted = true;
      }
      expiredDigestsFutures = builder.build();
    }

    ImmutableSet.Builder<Digest> builder = ImmutableSet.builder();
    for (ListenableFuture<Digest> expiredDigestFuture : expiredDigestsFutures) {
      Digest digest = getOrIOException(expiredDigestFuture);
      if (Thread.interrupted()) {
        interrupted = true;
      }
      if (digest != null) {
        builder.add(digest);
      }
    }
    Set<Digest> expiredDigests = builder.build();
    if (!expiredDigests.isEmpty()) {
      onExpire.accept(expiredDigests);
    }
    if (interrupted || Thread.currentThread().isInterrupted()) {
      throw new InterruptedException();
    }
    return true;
  }