#### Http2Writer

Socket writes are guarded by the Http2Writer. Only one stream can write at a time so that messages are not interleaved. Writes are either made by application-layer threads or the do-stuff-later pool.

### Holding multiple locks

            assertEquals(maxCount, dataService.getCount(sessionId2));

            UrlQueue urlQueue;
            while ((urlQueue = urlQueueService.poll(sessionId1)) != null) {
                assertTrue(urlQueue.getUrl().startsWith(url1));
            }
            while ((urlQueue = urlQueueService.poll(sessionId2)) != null) {
                assertTrue(urlQueue.getUrl().startsWith(url2));
            }

    @Override
    public Hasher putBytes(ByteBuffer buffer) {
      ByteOrder bo = buffer.order();
      buffer.order(ByteOrder.LITTLE_ENDIAN);
      while (buffer.remaining() >= 4) {
        putInt(buffer.getInt());
      }
      while (buffer.hasRemaining()) {
        putByte(buffer.get());
      }
      buffer.order(bo);
      return this;
    }

    @CanIgnoreReturnValue
    @Override

        }
        final StringBuilder buffer = new StringBuilder((int) Math.ceil(length / 3d) * 4);
        final int remainder = length % 3;
        length -= remainder;
        int block;
        int i = 0;
        while (i < length) {
            block = (bytes[i++] & 0xff) << 16 | (bytes[i++] & 0xff) << 8 | bytes[i++] & 0xff;
            buffer.append(ALPHABET.charAt(block >>> 18));
            buffer.append(ALPHABET.charAt(block >>> 12 & 0x3f));

        }
        fail("could not start job.");
    }

    protected static void waitJob(final String namePrefix) {
        Boolean isRunning = false;
        int count = 0;

        while (count < 300 && !isRunning) { // Wait until the crawler starts
            ThreadUtil.sleep(500);
            count++;
            final Map<String, Object> scheduler = getSchedulerItem(namePrefix);

          executor.execute(
              () -> {
                try {
                  startUp();
                  notifyStarted();
                  // If stopAsync() is called while starting we may be in the STOPPING state in
                  // which case we should skip right down to shutdown.
                  if (isRunning()) {
                    try {

          } catch (Exception e) { // sneaky checked exception
            log.get().log(Level.SEVERE, "Exception while executing runnable " + task, e);
          } finally {
            task = null;
          }
        }
      } finally {
        // Ensure that if the thread was interrupted at all while processing the task queue, it
        // is returned to the delegate Executor interrupted so that it may handle the

  }

  @Override
  public int read() throws IOException {
    while (in != null) {
      int result = in.read();
      if (result != -1) {
        return result;
      }
      advance();
    }
    return -1;
  }

  @Override
  public int read(byte[] b, int off, int len) throws IOException {
    checkNotNull(b);
    while (in != null) {
      int result = in.read(b, off, len);
      if (result != -1) {

    ImmutableMap.Builder<String, PublicSuffixType> builder = ImmutableMap.builder();
    int encodedLen = encoded.length();
    int idx = 0;

    while (idx < encodedLen) {
      idx += doParseTrieToBuilder(new ArrayDeque<>(), encoded, idx, builder);
    }

    return builder.buildOrThrow();
  }

  /**

            final String key = property.getKey();
            final StringBuilder value = new StringBuilder();
            final Iterator<String> values = property.getValue().iterator();
            while (values.hasNext()) {
                value.append(values.next());
                if (values.hasNext()) {
                    value.append(", ");
                }
            }