* maximumSize}, {@link #maximumWeight(long) maximumWeight}, {@link #expireAfterWrite
 * expireAfterWrite}, {@link #expireAfterAccess expireAfterAccess}, {@link #weakKeys weakKeys},
 * {@link #weakValues weakValues}, or {@link #softValues softValues} are requested.
 *
 * <p>If {@link #maximumSize(long) maximumSize} or {@link #maximumWeight(long) maximumWeight} is

    CountingLoader countingLoader = new CountingLoader();
    LoadingCache<Object, Object> cache =
        CacheBuilder.newBuilder().concurrencyLevel(1).weakKeys().build(countingLoader);

    Object key = new Object();
    assertNotNull(cache.getUnchecked(key));
    assertEquals(1, cache.size());

    CacheTesting.simulateKeyReclamation(cache, key);

    assertInvalid("http://.a/", "Invalid URL host: \".a\"")
    assertInvalid("http://../", "Invalid URL host: \"..\"")
  }

  @Test
  fun hostnameTelephone() {
    // https://www.gosecure.net/blog/2020/10/27/weakness-in-java-tls-host-verification/

    // Map the single character telephone symbol (℡) to the string "tel".
    assertThat(parse("http://\u2121").host).isEqualTo("tel")