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

    assertEquals(0L, map.getAndIncrement(key));
    assertEquals(1L, map.get(key));

    assertEquals(1L, map.getAndDecrement(key));
    assertEquals(0L, map.get(key));
    assertTrue(map.containsKey(key));

    assertEquals(0L, map.getAndIncrement(key));
    assertEquals(1L, map.get(key));
  }

  public void testDecrementAndGet() {

                      case 2:
                        map.addAndGet(key, delta);
                        threadSum += delta;
                        break;
                      case 3:
                        map.getAndIncrement(key);
                        threadSum++;
                        break;
                      case 4:
                        map.getAndDecrement(key);
                        threadSum--;

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

    assertEquals(0L, map.getAndIncrement(key));
    assertEquals(1L, map.get(key));

    assertEquals(1L, map.getAndDecrement(key));
    assertEquals(0L, map.get(key));
    assertTrue(map.containsKey(key));

    assertEquals(0L, map.getAndIncrement(key));
    assertEquals(1L, map.get(key));
  }

  public void testDecrementAndGet() {

                      case 2:
                        map.addAndGet(key, delta);
                        threadSum += delta;
                        break;
                      case 3:
                        map.getAndIncrement(key);
                        threadSum++;
                        break;
                      case 4:
                        map.getAndDecrement(key);
                        threadSum--;

      for (int i = 0; i < passedArgs.length; i++) {
        assertEquals(
            "Parameter #" + i + " of " + method + " not forwarded", passedArgs[i], args[i]);
      }
      called.getAndIncrement();
      return returnValue;
    }

    void testInteraction(Function<? super T, ? extends T> wrapperFunction) {
      T proxy = Reflection.newProxy(interfaceType, this);

      for (int i = 0; i < passedArgs.length; i++) {
        assertEquals(
            "Parameter #" + i + " of " + method + " not forwarded", passedArgs[i], args[i]);
      }
      called.getAndIncrement();
      return returnValue;
    }

    void testInteraction(Function<? super T, ? extends T> wrapperFunction) {
      T proxy = Reflection.newProxy(interfaceType, this);

                            + " synchronizing on supplier"));
                break;
              }
              Thread.yield();
            }
            count.getAndIncrement();
            return Boolean.TRUE;
          }
        };

    final Supplier<Boolean> memoizedSupplier = memoizer.apply(supplier);

    for (int i = 0; i < numThreads; i++) {
      threads[i] =

                            + " synchronizing on supplier"));
                break;
              }
              Thread.yield();
            }
            count.getAndIncrement();
            return Boolean.TRUE;
          }
        };

    final Supplier<Boolean> memoizedSupplier = memoizer.apply(supplier);

    for (int i = 0; i < numThreads; i++) {
      threads[i] =

        // One or more integer values could be skipped in the event of a race
        // to generate a UID for the same object from multiple threads, but
        // that shouldn't be a problem.
        uid = counter.getAndIncrement();
        Integer alreadySet = uids.putIfAbsent(obj, uid);
        if (alreadySet != null) {
          uid = alreadySet;
        }
      }
      return uid;
    }

    @Override

        // value changed
      }
    }
  }

  /**
   * Increments by one the value currently associated with {@code key}, and returns the old value.
   */
  @CanIgnoreReturnValue
  public long getAndIncrement(K key) {
    return getAndAdd(key, 1);
  }

  /**
   * Decrements by one the value currently associated with {@code key}, and returns the old value.
   */
  @CanIgnoreReturnValue