*
 * @author Charles Fry
 */
public class LoadingCacheSingleThreadBenchmark {
  @Param({"1000", "2000"})
  int maximumSize;

  @Param("5000")
  int distinctKeys;

  @Param("4")
  int segments;

  // 1 means uniform likelihood of keys; higher means some keys are more popular
  // tweak this to control hit rate
  @Param("2.5")
  double concentration;

  Random random = new Random();

   * {@link #splitToList(CharSequence)}. Java 8+ users may prefer {@link #splitToStream} instead.
   *
   * @param sequence the sequence of characters to split
   * @return an iteration over the segments split from the parameter
   */
  public Iterable<String> split(final CharSequence sequence) {
    checkNotNull(sequence);

    return new Iterable<String>() {
      @Override

 *
 * <ul>
 *   <li>automatic loading of entries into the cache
 *   <li>least-recently-used eviction when a maximum size is exceeded (note that the cache is
 *       divided into segments, each of which does LRU internally)
 *   <li>time-based expiration of entries, measured since last access or last write
 *   <li>keys automatically wrapped in {@code WeakReference}

    LocalCache<?, ?> map = CacheTesting.toLocalCache(cache);

    assertThat(map.segments).hasLength(4);
    assertEquals(2, map.segments[0].table.length());
    assertEquals(2, map.segments[1].table.length());
    assertEquals(2, map.segments[2].table.length());
    assertEquals(2, map.segments[3].table.length());
  }

  @GwtIncompatible // CacheTesting
  public void testInitialCapacity_smallest() {

  void setUp() {
    LocalCache<Object, Object> cache =
        new LocalCache<>(
            CacheBuilder.newBuilder().concurrencyLevel(1).initialCapacity(capacity), null);
    checkState(cache.segments.length == 1);
    segment = cache.segments[0];
    checkState(segment.table.length() == capacity);
    for (int i = 0; i < segment.threshold; i++) {
      cache.put(new Object(), new Object());
    }

    // of the values gets evicted. With weak keys, we use identity equality, which means using
    // System.identityHashCode, which means the assignment of keys to segments is nondeterministic,
    // so more than (maximumSize / #segments) keys could get assigned to the same segment, which
    // would cause one to be evicted.
    return new CacheBuilderFactory()

        createCacheBuilder().concurrencyLevel(1).maximumSize(SMALL_MAX_SIZE);
    LocalLoadingCache<Object, Object> cache = makeCache(builder, identityLoader());
    Segment<Object, Object> segment = cache.localCache.segments[0];
    ConcurrentMap<Object, Object> map = cache.asMap();

    Object one = new Object();
    assertSame(one, cache.getUnchecked(one));
    assertTrue(segment.recencyQueue.isEmpty());