}


  public void testInvalidate_empty() {
    for (LoadingCache<Object, Object> cache : caches()) {
      cache.getUnchecked("a");
      cache.getUnchecked("b");
      cache.invalidate("a");
      cache.invalidate("b");
      cache.invalidate(0);
      checkEmpty(cache);
    }
  }

  public void testInvalidateAll_empty() {
    for (LoadingCache<Object, Object> cache : caches()) {
      cache.getUnchecked("a");

    cache.put(0, 10);

    assertEquals(Integer.valueOf(10), cache.get(0, loader));
    assertEquals(Integer.valueOf(1), cache.get(20, loader));
    assertEquals(Integer.valueOf(2), cache.get(34, loader));

    cache.invalidate(0);
    assertEquals(Integer.valueOf(3), cache.get(0, loader));

    cache.put(0, 10);
    cache.invalidateAll();
    assertEquals(Integer.valueOf(4), cache.get(0, loader));
  }

      Key key2 = new Key(2);
      String value2 = key2.toString();
      assertSame(value1, cache.getUnchecked(key1));
      assertSame(value2, cache.getUnchecked(key2));
      cache.invalidate(key1);
      assertFalse(cache.asMap().containsKey(key1));
      assertTrue(cache.asMap().containsKey(key2));
      assertEquals(1, cache.size());
      assertEquals(ImmutableSet.of(key2), cache.asMap().keySet());

    cache.put(0, 10);

    assertEquals(Integer.valueOf(10), cache.get(0, loader));
    assertEquals(Integer.valueOf(1), cache.get(20, loader));
    assertEquals(Integer.valueOf(2), cache.get(34, loader));

    cache.invalidate(0);
    assertEquals(Integer.valueOf(3), cache.get(0, loader));

    cache.put(0, 10);
    cache.invalidateAll();
    assertEquals(Integer.valueOf(4), cache.get(0, loader));
  }

    assertThat(wrappedSet).isEqualTo(copyOfWrappedSet);

    // test that setToTest is still valid
    assertThat(setToTest).isEqualTo(wrappedSet);
    assertThat(setToTest).isEqualTo(copyOfWrappedSet);

    // invalidate setToTest
    wrappedSet.remove(1);
    // sanity check on update of wrappedSet
    assertThat(wrappedSet).isNotEqualTo(copyOfWrappedSet);

    assertThat(wrappedSet).isEqualTo(copyOfWrappedSet);

    // test that setToTest is still valid
    assertThat(setToTest).isEqualTo(wrappedSet);
    assertThat(setToTest).isEqualTo(copyOfWrappedSet);

    // invalidate setToTest
    wrappedSet.remove(1);
    // sanity check on update of wrappedSet
    assertThat(wrappedSet).isNotEqualTo(copyOfWrappedSet);

    cache.invalidateAll(toInvalidate);
    assertEquals(toInvalidate, invalidated);
  }

  public void testEmptySimpleStats() {
    StatsCounter counter = new SimpleStatsCounter();
    CacheStats stats = counter.snapshot();
    assertEquals(0, stats.requestCount());
    assertEquals(0, stats.hitCount());
    assertEquals(1.0, stats.hitRate());
    assertEquals(0, stats.missCount());

        new Receiver<ReferenceEntry<Integer, Integer>>() {
          @Override
          public void accept(ReferenceEntry<Integer, Integer> entry) {
            Integer key = entry.getKey();
            cache.invalidate(key);
          }
        });
  }

  public void testEviction_lru() {
    // test lru within a single segment
    IdentityLoader<Integer> loader = identityLoader();

 * @since 10.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public enum RemovalCause {
  /**
   * The entry was manually removed by the user. This can result from the user invoking {@link
   * Cache#invalidate}, {@link Cache#invalidateAll(Iterable)}, {@link Cache#invalidateAll()}, {@link
   * Map#remove}, {@link ConcurrentMap#remove}, or {@link Iterator#remove}.
   */
  EXPLICIT {
    @Override
    boolean wasEvicted() {

   *
   * @since 12.0
   */
  void putAll(Map<? extends K, ? extends V> m);

  /** Discards any cached value for key {@code key}. */
  void invalidate(@CompatibleWith("K") Object key);

  /**
   * Discards any cached values for keys {@code keys}.
   *
   * @since 11.0
   */
  // For discussion of <? extends Object>, see getAllPresent.