}

  /**
   * Returns a predicate that evaluates to {@code true} if the object reference being tested is
   * null.
   *
   * <p><b>Discouraged:</b> Prefer using either {@code x -> x == null} or {@code Objects::isNull},
   * but note that lambdas and method references do not have human-readable {@link #toString()}
   * representations and are not serializable.
   */

  }

  /**
   * Returns an unmodifiable view of the specified collection, preserving the interface for
   * instances of {@code SortedSet}, {@code Set}, {@code List} and {@code Collection}, in that order
   * of preference.
   *
   * @param collection the collection for which to return an unmodifiable view
   * @return an unmodifiable view of the collection
   */

  }

  /**
   * Returns an unmodifiable view of the specified collection, preserving the interface for
   * instances of {@code SortedSet}, {@code Set}, {@code List} and {@code Collection}, in that order
   * of preference.
   *
   * @param collection the collection for which to return an unmodifiable view
   * @return an unmodifiable view of the collection
   */

      return created;
    }

    // N.B. Draining the queue is only necessary to ensure that we don't accumulate empty references
    // in the array. We could skip this if we decide we don't care about holding on to Reference
    // objects indefinitely.
    private void drainQueue() {
      Reference<? extends L> ref;
      while ((ref = queue.poll()) != null) {

  /*
   * We avoid using a method reference or lambda here for now:
   *
   * - method reference: Inside Google, CacheBuilder is used from the implementation of a custom
   *   ClassLoader that is sometimes used as a system classloader. That's a problem because
   *   method-reference linking tries to look up the system classloader, and it fails because there
   *   isn't one yet.
   *

      }
    }
  }

  /** A weakly referenced value that also has a reference to its containing entry. */
  interface WeakValueReference<K, V, E extends InternalEntry<K, V, E>> {
    /**
     * Returns the current value being referenced, or {@code null} if there is none (e.g. because

  }

  /**
   * Returns a new array of the given length with the same type as a reference array.
   *
   * @param reference any array of the desired type
   * @param length the length of the new array
   */
  public static <T extends @Nullable Object> T[] newArray(T[] reference, int length) {
    return Platform.newArray(reference, length);
  }

  /**

  }

  /**
   * Returns a new array of the given length with the same type as a reference array.
   *
   * @param reference any array of the desired type
   * @param length the length of the new array
   */
  public static <T extends @Nullable Object> T[] newArray(T[] reference, int length) {
    return Platform.newArray(reference, length);
  }

  /**

 *       However, the precise conditions for skipping the copy operation are undefined.
 *   <li><b>Warning:</b> a view collection such as {@link ImmutableMap#keySet} or {@link
 *       ImmutableList#subList} may retain a reference to the entire data set, preventing it from
 *       being garbage collected. If some of the data is no longer reachable through other means,

    Object[] reference = list.toArray(array1);

    Object[] target = ObjectArrays.toArrayImpl(list, array2);

    assertEquals(reference.getClass(), target.getClass());
    assertTrue(Arrays.equals(reference, target));
    assertTrue(Arrays.equals(reference, target));

    Object[] expectedArray1 = expectModify ? reference : starting;