assertSame(value, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertFalse(segment.containsValue(nullValue));

    // hash collision
    InternalEntry<Object, Object, ?> dummyEntry =
        segment.newEntryForTesting(new Object(), hash, entry);
    Object dummyValue = new Object();
    WeakValueReference<Object, Object, ?> dummyValueRef =

    assertSame(value, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertFalse(segment.containsValue(nullValue));

    // hash collision
    InternalEntry<Object, Object, ?> dummyEntry =
        segment.newEntryForTesting(new Object(), hash, entry);
    Object dummyValue = new Object();
    WeakValueReference<Object, Object, ?> dummyValueRef =

 *       they appear. Input data is never modified. {@link HashFunction} instances should always be
 *       stateless, and therefore thread-safe.
 *   <li><b>collision-averse:</b> while it can't be helped that a hash function will sometimes
 *       produce the same hash code for distinct inputs (a "collision"), every hash function strives
 *       to <i>some</i> degree to make this unlikely. (Without this condition, a function that

   *
   * Per-thread hash codes are initialized to random values.
   * Contention and/or table collisions are indicated by failed
   * CASes when performing an update operation (see method
   * retryUpdate). Upon a collision, if the table size is less than
   * the capacity, it is doubled in size unless some other thread
   * holds the lock. If a hashed slot is empty, and lock is
   * available, a new Cell is created. Otherwise, if the slot

    assertSame(value, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertFalse(segment.containsValue(nullValue));

    // hash collision
    DummyEntry<Object, Object> dummy = DummyEntry.create(new Object(), hash, entry);
    Object dummyValue = new Object();
    ValueReference<Object, Object> dummyValueRef = map.newValueReference(dummy, dummyValue, 1);

    assertSame(value, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertFalse(segment.containsValue(nullValue));

    // hash collision
    DummyEntry<Object, Object> dummy = DummyEntry.create(new Object(), hash, entry);
    Object dummyValue = new Object();
    ValueReference<Object, Object> dummyValueRef = map.newValueReference(dummy, dummyValue, 1);

   *
   * Per-thread hash codes are initialized to random values.
   * Contention and/or table collisions are indicated by failed
   * CASes when performing an update operation (see method
   * retryUpdate). Upon a collision, if the table size is less than
   * the capacity, it is doubled in size unless some other thread
   * holds the lock. If a hashed slot is empty, and lock is
   * available, a new Cell is created. Otherwise, if the slot

        // probably intended. So no point in using an equal-but-different factory argument.
        // We check twice to avoid confusion caused by accidental hash collision.
        equalArgs.set(i, shouldBeEqualArg);
      }
    }
    return equalArgs;
  }

  private static boolean hashCodeInsensitiveToArgReference(

    // TABLE is a precomputed hashset of whitespace characters. MULTIPLIER serves as a hash function
    // whose key property is that it maps 25 characters into the 32-slot table without collision.
    // Basically this is an opportunistic fast implementation as opposed to "good code". For most
    // other use-cases, the reduction in readability isn't worth it.
    static final String TABLE =

      int leftCode = identityHashCode(left);
      int rightCode = identityHashCode(right);
      if (leftCode != rightCode) {
        return leftCode < rightCode ? -1 : 1;
      }

      // identityHashCode collision (rare, but not as rare as you'd think)
      int result = getUid(left).compareTo(getUid(right));
      if (result == 0) {
        throw new AssertionError(); // extremely, extremely unlikely.
      }