@Override
    public void run() {}
  }
  // The thread executing the task publishes itself to the superclass' reference and the thread
  // interrupting sets DONE when it has finished interrupting.
  private static final Runnable DONE = new DoNothingRunnable();
  private static final Runnable PARKED = new DoNothingRunnable();
  // Why 1000?  WHY NOT!
  private static final int MAX_BUSY_WAIT_SPINS = 1000;

  protected AbstractIterator() {}

  private enum State {
    READY,
    NOT_READY,
    DONE,
    FAILED,
  }

  @CheckForNull private T next;

  @CheckForNull
  protected abstract T computeNext();

  @CanIgnoreReturnValue
  @CheckForNull
  protected final T endOfData() {
    state = State.DONE;
    return null;
  }

  @Override
  public final boolean hasNext() {

        crawlerStatsHelper.done(key);
        logger.info(localLogMsg.get());
        String[] values = localLogMsg.get().split("\t");
        assertEquals(3, values.length);
        assertEquals("url:test", values[0]);
        assertTrue(values[1].startsWith("time:"));
        assertTrue(values[2].startsWith("done:"));

        localLogMsg.remove();
        crawlerStatsHelper.done(key);
        assertNull(localLogMsg.get());

      checkNotDone();
      checkNotNull(bytes);
      mac.update(bytes);
    }

    private void checkNotDone() {
      checkState(!done, "Cannot re-use a Hasher after calling hash() on it");
    }

    @Override
    public HashCode hash() {
      checkNotDone();
      done = true;
      return HashCode.fromBytesNoCopy(mac.doFinal());
    }
  }

                buf.append('\t').append("action:done");
                buf.append('\t').append("error:").append(escapeValue(e.getLocalizedMessage()).replaceAll("\\s", " "));
                log(buf);
            }
        });
    }

    protected void printStats(final Object keyObj, final StatsObject data, final long begin, final boolean done) {
        final StringBuilder buf = createStringBuffer(keyObj, begin);

    protected static final String SUFFIX = ".tmp";

    protected boolean done = false;

    public ContentOutputStream(final int threshold, final File tmpDir) {
        super(threshold, PREFIX, SUFFIX, tmpDir);
    }

    @Override
    public File getFile() {
        done = true;
        return super.getFile();
    }

    @Override
    public void close() throws IOException {

        assertFalse(cos.done);
        assertTrue(cos.isInMemory());
        cos.close();
        assertFalse(cos.done);
    }

    @Test
    public void inFile() throws IOException {
        ContentOutputStream cos = new ContentOutputStream(10, Curl.tmpDir);
        cos.write(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 });
        assertFalse(cos.done);
        assertFalse(cos.isInMemory());

    return new TrackedRunnable() {
      private volatile boolean done = false;

      @Override
      public boolean isDone() {
        return done;
      }

      @Override
      public void run() {
        try {
          delay(timeoutMillis);
          done = true;
        } catch (InterruptedException ok) {
        }
      }
    };
  }

      checkNotDone();
      digest.update(bytes);
    }

    private void checkNotDone() {
      checkState(!done, "Cannot re-use a Hasher after calling hash() on it");
    }

    @Override
    public HashCode hash() {
      checkNotDone();
      done = true;
      return (bytes == digest.getDigestLength())
          ? HashCode.fromBytesNoCopy(digest.digest())

   */
  @CanIgnoreReturnValue
  @CheckForNull
  protected final T endOfData() {
    state = State.DONE;
    return null;
  }

  @Override
  public final boolean hasNext() {
    checkState(state != State.FAILED);
    switch (state) {
      case DONE:
        return false;
      case READY:
        return true;
      default:
    }
    return tryToComputeNext();
  }