checkArgument(maximumSize >= 0, "maximum size must not be negative");
    this.maximumSize = maximumSize;
    return this;
  }

  /**
   * Specifies the maximum weight of entries the cache may contain. Weight is determined using the
   * {@link Weigher} specified with {@link #weigher}, and use of this method requires a

  /** Returns a {@link Weigher} that returns the given {@code constant} for every request. */
  static Weigher<Object, Object> constantWeigher(int constant) {
    return new ConstantWeigher(constant);
  }

  /** Returns a {@link Weigher} that uses the integer key as the weight. */
  static Weigher<Integer, Object> intKeyWeigher() {
    return new IntKeyWeigher();
  }

  }

  public void testSetWeigher() {
    Weigher<Object, Object> testWeigher =
        new Weigher<Object, Object>() {
          @Override
          public int weigh(Object key, Object value) {
            return 42;
          }
        };
    LocalCache<Object, Object> map =
        makeLocalCache(createCacheBuilder().maximumWeight(1).weigher(testWeigher));
    assertSame(testWeigher, map.weigher);
  }

  }

  public void testEviction_weightedLru() {
    // test weighted lru within a single segment
    IdentityLoader<Integer> loader = identityLoader();
    LoadingCache<Integer, Integer> cache =
        CacheBuilder.newBuilder()
            .concurrencyLevel(1)
            .maximumWeight(45)
            .weigher(intKeyWeigher())
            .build(loader);
    CacheTesting.warmUp(cache, 0, 10);

  }

  @GwtIncompatible // weigher
  public void testWeigher_withoutMaximumWeight() {
    CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder().weigher(constantWeigher(42));
    assertThrows(IllegalStateException.class, () -> builder.build(identityLoader()));
  }

  @GwtIncompatible // weigher
  public void testWeigher_withMaximumSize() {
    assertThrows(

  }

  @GwtIncompatible // weigher
  public void testWeigher_withoutMaximumWeight() {
    CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder().weigher(constantWeigher(42));
    assertThrows(IllegalStateException.class, () -> builder.build(identityLoader()));
  }

  @GwtIncompatible // weigher
  public void testWeigher_withMaximumSize() {
    assertThrows(

   * array nor its contents can be null, but it is not useful to force the use of {@code
   * requireNonNull} or the like just to assert that.
   *
   * <p>{@code EqualsTester} will always check that every object it is given returns false from
   * {@code equals(null)}, so it is neither useful nor allowed to include a null value in any
   * equality group.
   */

   * non-null, it should be reported to the user should all further attempts fail.
   *
   * The two values are independent: results can contain both (recoverable error), neither
   * (success), just an exception (permanent failure), or just a plan (non-exceptional retry).
   */
  data class ConnectResult(
    val plan: Plan,
    val nextPlan: Plan? = null,

 * Double#POSITIVE_INFINITY POSITIVE_INFINITY} sort to the beginning and the end of the dataset, as
 * you would expect.
 *
 * <p>If required to do a weighted average between an infinity and a finite value, or between an
 * infinite value and itself, the infinite value is returned. If required to do a weighted average
 * between {@link Double#NEGATIVE_INFINITY NEGATIVE_INFINITY} and {@link Double#POSITIVE_INFINITY

        if (this.equivalence.equals(that.equivalence)) {
          /*
           * We'll accept that as sufficient "proof" that either equivalence should be able to
           * handle either reference, so it's safe to circumvent compile-time type checking.
           */
          @SuppressWarnings("unchecked")