assertEquals(0L, map.get(key));
    assertFalse(map.containsKey(key));

    assertEquals(-1L, map.decrementAndGet(key));
    assertEquals(-1L, map.get(key));

    assertEquals(0L, map.incrementAndGet(key));
    assertEquals(0L, map.get(key));
    assertTrue(map.containsKey(key));

    assertEquals(-1L, map.decrementAndGet(key));
    assertEquals(-1L, map.get(key));
  }

  public void testGetAndDecrement() {

    // by executing on the same thread.
    if (executorService.isShutdown) {
      for (i in 0 until executableCalls.size) {
        val asyncCall = executableCalls[i]
        asyncCall.callsPerHost.decrementAndGet()

        this.withLock {
          runningAsyncCalls.remove(asyncCall)
        }

        asyncCall.failRejected()
      }
      idleCallback?.run()
    } else {

                      case 0:
                        map.incrementAndGet(key);
                        threadSum++;
                        break;
                      case 1:
                        map.decrementAndGet(key);
                        threadSum--;
                        break;
                      case 2:
                        map.addAndGet(key, delta);
                        threadSum += delta;

    }

    public long incrementAndGetAccessCount() {
        return accessCount.incrementAndGet();
    }

    public long decrementAndGetAccessCount() {
        return accessCount.decrementAndGet();
    }

    public CrawlerStatus getStatus() {
        return status;
    }

    public void setStatus(final CrawlerStatus status) {
        this.status = status;
    }

     * 
     * @throws SmbException
     *
     * @see jcifs.SmbFileHandle#release()
     */
    @Override
    public synchronized void release () throws CIFSException {
        long usage = this.usageCount.decrementAndGet();
        if ( usage == 0 ) {
            closeInternal(0L, false);
        }
        else if ( log.isTraceEnabled() ) {
            log.trace(String.format("Release %s (%d)", this, usage));
        }

            this.treeConnection.acquire();
        }
        return this;
    }


    @Override
    public void release () {
        long us = this.usageCount.decrementAndGet();
        if ( us == 0 ) {
            this.treeConnection.release();
        }
        else if ( us < 0 ) {
            throw new RuntimeCIFSException("Usage count dropped below zero");
        }
    }

      seenExceptionsUpdater.compareAndSet(state, expect, update);
    }

    @Override
    int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
      return remainingCountUpdater.decrementAndGet(state);
    }
  }

  private static final class SynchronizedAtomicHelper extends AtomicHelper {
    @Override
    void compareAndSetSeenExceptions(

      seenExceptionsUpdater.compareAndSet(state, expect, update);
    }

    @Override
    int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
      return remainingCountUpdater.decrementAndGet(state);
    }
  }

  private static final class SynchronizedAtomicHelper extends AtomicHelper {
    @Override
    void compareAndSetSeenExceptions(

            count = new AtomicInteger(1);
        }

        public int increment() {
            return count.incrementAndGet();
        }

        public int decrement() {
            return count.decrementAndGet();
        }
    }

    public enum StatsAction {
        ACCESSED, //
        ACCESS_EXCEPTION, //
        CHILD_URL, //
        CHILD_URLS, //
        EVALUATED, //
        EXCEPTION, //

    return addAndGet(key, 1);
  }

  /**
   * Decrements by one the value currently associated with {@code key}, and returns the new value.
   */
  @CanIgnoreReturnValue
  public long decrementAndGet(K key) {
    return addAndGet(key, -1);
  }

  /**
   * Adds {@code delta} to the value currently associated with {@code key}, and returns the new
   * value.
   */
  @CanIgnoreReturnValue