*
   * @throws IllegalArgumentException if {@code concurrencyLevel} is nonpositive
   * @throws IllegalStateException if a concurrency level was already set
   */
  @CanIgnoreReturnValue
  public MapMaker concurrencyLevel(int concurrencyLevel) {
    checkState(
        this.concurrencyLevel == UNSET_INT,
        "concurrency level was already set to %s",
        this.concurrencyLevel);
    checkArgument(concurrencyLevel > 0);

    }
  }

  /** Parse concurrencyLevel */
  private static final class ConcurrencyLevelParser extends IntegerParser {
    @Override
    void parseInteger(CacheBuilderSpec spec, int value) {
      checkArgument(
          spec.concurrencyLevel == null,
          "concurrency level was already set to %s",
          spec.concurrencyLevel);
      spec.concurrencyLevel = value;
    }
  }

    }
  }

  /** Parse concurrencyLevel */
  private static final class ConcurrencyLevelParser extends IntegerParser {
    @Override
    void parseInteger(CacheBuilderSpec spec, int value) {
      checkArgument(
          spec.concurrencyLevel == null,
          "concurrency level was already set to %s",
          spec.concurrencyLevel);
      spec.concurrencyLevel = value;
    }
  }

   *
   * @throws IllegalArgumentException if {@code concurrencyLevel} is nonpositive
   * @throws IllegalStateException if a concurrency level was already set
   */
  @CanIgnoreReturnValue
  public MapMaker concurrencyLevel(int concurrencyLevel) {
    checkState(
        this.concurrencyLevel == UNSET_INT,
        "concurrency level was already set to %s",
        this.concurrencyLevel);
    checkArgument(concurrencyLevel > 0);

    checkConcurrencyLevel(7, 8);
    checkConcurrencyLevel(8, 8);
  }

  private static void checkConcurrencyLevel(int concurrencyLevel, int segmentCount) {
    MapMakerInternalMap<Object, Object, ?, ?> map =
        makeMap(createMapMaker().concurrencyLevel(concurrencyLevel));
    assertThat(map.segments).hasLength(segmentCount);
  }

  public void testSetInitialCapacity() {

    checkConcurrencyLevel(7, 8);
    checkConcurrencyLevel(8, 8);
  }

  private static void checkConcurrencyLevel(int concurrencyLevel, int segmentCount) {
    MapMakerInternalMap<Object, Object, ?, ?> map =
        makeMap(createMapMaker().concurrencyLevel(concurrencyLevel));
    assertThat(map.segments).hasLength(segmentCount);
  }

  public void testSetInitialCapacity() {

    }
  }

  public void testEviction_maxSizeOneSegment() {
    IdentityLoader<Integer> loader = identityLoader();
    LoadingCache<Integer, Integer> cache =
        CacheBuilder.newBuilder().concurrencyLevel(1).maximumSize(MAX_SIZE).build(loader);
    for (int i = 0; i < 2 * MAX_SIZE; i++) {
      cache.getUnchecked(i);
      assertThat(cache.size()).isEqualTo(min(i + 1, MAX_SIZE));
    }

  }

  public void testEqualsAndHashCode() {
    new EqualsTester()
        .addEqualityGroup(parse(""), parse(""))
        .addEqualityGroup(parse("concurrencyLevel=7"), parse("concurrencyLevel=7"))
        .addEqualityGroup(parse("concurrencyLevel=15"), parse("concurrencyLevel=15"))
        .addEqualityGroup(parse("initialCapacity=7"), parse("initialCapacity=7"))
        .addEqualityGroup(parse("initialCapacity=15"), parse("initialCapacity=15"))

    tester.testAllPublicInstanceMethods(makeCache(createCacheBuilder(), loader));
  }

  // stats tests

  public void testStats() {
    CacheBuilder<Object, Object> builder = createCacheBuilder().concurrencyLevel(1).maximumSize(2);
    LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
    assertThat(cache.stats()).isEqualTo(EMPTY_STATS);

    Object one = new Object();
    cache.getUnchecked(one);

    tester.testAllPublicInstanceMethods(makeCache(createCacheBuilder(), loader));
  }

  // stats tests

  public void testStats() {
    CacheBuilder<Object, Object> builder = createCacheBuilder().concurrencyLevel(1).maximumSize(2);
    LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
    assertThat(cache.stats()).isEqualTo(EMPTY_STATS);

    Object one = new Object();
    cache.getUnchecked(one);