*
 * ### Username and Password
 *
 * Username and password are either present, or the empty string `""` if absent. This class offers
 * no mechanism to differentiate empty from absent. Neither of these components are popular in
 * practice. Typically HTTP applications use other mechanisms for user identification and
 * authentication.
 *
 * ### Host
 *

    could use new flow control capacity before acknowledging it, causing strict HTTP/2 servers to
    fail the call.


## Version 3.12.4

_2019-09-04_

 *  Fix: Don't crash looking up an absent class on certain buggy Android 4.x devices.


## Version 3.12.3

_2019-05-07_

 *  Fix: Permit multipart file names to contain non-ASCII characters.

    set("k1", "a", "a")
    cache["k1"]!!.use {
      cache.remove("k1")
      assertThat(cache.edit("k1")).isNull()
    }
  }

  @Test
  fun `removed entry absent when iterating`() {
    set("k1", "a", "a")
    cache["k1"]!!.use {
      cache.remove("k1")
      val snapshots = cache.snapshots()
      assertThat(snapshots.hasNext()).isFalse()
    }
  }

    checkNotNull(predicate);
    while (iterator.hasNext()) {
      T t = iterator.next();
      if (predicate.apply(t)) {
        return Optional.of(t);
      }
    }
    return Optional.absent();
  }

  /**
   * Returns the index in {@code iterator} of the first element that satisfies the provided {@code
   * predicate}, or {@code -1} if the Iterator has no such elements.
   *

        '`'.code,
        '{'.code,
        '|'.code,
        '}'.code,
      ).test(UrlComponentEncodingTester.Component.HOST)
  }

  @Test
  fun hostIpv6() {
    // Square braces are absent from host()...
    assertThat(parse("http://[::1]/").host).isEqualTo("::1")

    // ... but they're included in toString().
    assertThat(parse("http://[::1]/").toString()).isEqualTo("http://[::1]/")