cacheEntry1 = null;
    cacheEntry2 = null;
  }

  private void addToCache(K key, V value) {
    addToCache(new CacheEntry<K, V>(key, value));
  }

  private void addToCache(CacheEntry<K, V> entry) {
    // Slide new entry into first cache position. Drop previous entry in second cache position.
    cacheEntry2 = cacheEntry1;
    cacheEntry1 = entry;
  }

  private static final class CacheEntry<K, V> {
    final K key;

    cacheEntry1 = null;
    cacheEntry2 = null;
  }

  private void addToCache(K key, V value) {
    addToCache(new CacheEntry<K, V>(key, value));
  }

  private void addToCache(CacheEntry<K, V> entry) {
    // Slide new entry into first cache position. Drop previous entry in second cache position.
    cacheEntry2 = cacheEntry1;
    cacheEntry1 = entry;
  }

  private static final class CacheEntry<K, V> {
    final K key;

    final E[] items = this.items;
    // if removing front item, just advance
    if (i == takeIndex) {
      items[takeIndex] = null;
      takeIndex = inc(takeIndex);
    } else {
      // slide over all others up through putIndex.
      for (; ; ) {
        int nexti = inc(i);
        if (nexti != putIndex) {
          items[i] = items[nexti];
          i = nexti;
        } else {

    final E[] items = this.items;
    // if removing front item, just advance
    if (i == takeIndex) {
      items[takeIndex] = null;
      takeIndex = inc(takeIndex);
    } else {
      // slide over all others up through putIndex.
      for (; ; ) {
        int nexti = inc(i);
        if (nexti != putIndex) {
          items[i] = items[nexti];
          i = nexti;
        } else {

  }

  /**
   * Returns a view of a slice of this byte source that is at most {@code length} bytes long
   * starting at the given {@code offset}. If {@code offset} is greater than the size of this
   * source, the returned source will be empty. If {@code offset + length} is greater than the size
   * of this source, the returned source will contain the slice starting at {@code offset} and
   * ending at the end of this source.

 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;

/**
 * Dummy class that makes the GWT serialization policy happy. It isn't used on the server-side.
 *
 * @author Hayward Chan
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
class ForwardingImmutableCollection {
  private ForwardingImmutableCollection() {}

        from = partitionPoint + 1;
      }
    }
  }

  /**
   * Performs a partition operation on the slice of {@code array} with elements in the range [{@code
   * from}, {@code to}]. Uses the median of {@code from}, {@code to}, and the midpoint between them
   * as a pivot. Returns the index which the slice is partitioned around, i.e. if it returns {@code

      label: 3. What would that same code look like if we added your feature?
    validations:
      required: true

  - type: markdown
    attributes:
      value: >
        Comparing two approaches to a use case side by side can make it easier to examine the
        differences between them.


        Additionally, it's very useful to us if you can provide a "straw API" — what the

    assertThrows(
        "expected IllegalArgumentException for call to slice with offset -1: " + source,
        IllegalArgumentException.class,
        () -> source.slice(-1, 0));

    assertThrows(
        "expected IllegalArgumentException for call to slice with length -1: " + source,
        IllegalArgumentException.class,
        () -> source.slice(0, -1));
  }

   * class documentation above). This method is <i>generally expected</i>, but not absolutely
   * required, to have the following properties:
   *
   * <ul>
   *   <li>Its execution does not cause any observable side effects.
   *   <li>The computation is <i>consistent with equals</i>; that is, {@link Objects#equal
   *       Objects.equal}{@code (a, b)} implies that {@code predicate.apply(a) ==
   *       predicate.apply(b))}.
   * </ul>