* or response.
 *
 * Implementations of this interface throw [IOException] to signal connectivity failures. This
 * includes both natural exceptions such as unreachable servers, as well as synthetic exceptions
 * when responses are of an unexpected type or cannot be decoded.
 *
 * Other exception types cancel the current call:
 *

      "http://[0.0.0.0:0:0:0:0:0:1]/",
      "Invalid URL host: \"[0.0.0.0:0:0:0:0:0:1]\"",
    )
  }

  @Test
  fun hostIpv6WithIncompleteIpv4Suffix() {
    // To Chrome & Safari these are well-formed; Firefox disagrees. (We're consistent with Firefox).
    assertInvalid(
      "http://[0:0:0:0:0:1:255.255.255.]/",
      "Invalid URL host: \"[0:0:0:0:0:1:255.255.255.]\"",
    )
    assertInvalid(

private val TYPE_SUBTYPE = Regex("$TOKEN/$TOKEN")
private val PARAMETER = Regex(";\\s*(?:$TOKEN=(?:$TOKEN|$QUOTED))?")

/**
 * Returns a media type for this string.
 *
 * @throws IllegalArgumentException if this is not a well-formed media type.
 */
internal fun String.commonToMediaType(): MediaType {
  val typeSubtype: MatchResult =
    TYPE_SUBTYPE.matchAtPolyfill(this, 0)
      ?: throw IllegalArgumentException("No subtype found for: \"$this\"")

      }

      // If this response shouldn't have been stored, it should never be used as a response source.
      // This check should be redundant as long as the persistence store is well-behaved and the
      // rules are constant.
      if (!isCacheable(cacheResponse, request)) {
        return CacheStrategy(request, null)
      }

      val requestCaching = request.cacheControl

 * or network should be done asynchronously.
 */
abstract class EventListener {
  /**
   * Invoked as soon as a call is enqueued or executed by a client. In case of thread or stream
   * limits, this call may be executed well before processing the request is able to begin.
   *
   * This will be invoked only once for a single [Call]. Retries of different routes or redirects

    /**
     * Returns a media type for this string.
     *
     * @throws IllegalArgumentException if this is not a well-formed media type.
     */
    @JvmStatic
    @JvmName("get")
    fun String.toMediaType(): MediaType = commonToMediaType()

    /** Returns a media type for this, or null if this is not a well-formed media type. */
    @JvmStatic
    @JvmName("parse")

signs the other party's chain.

Well-Known Certificate Authorities
----------------------------------

In these examples we've prearranged which root certificates to trust. But for regular HTTPS on the
Internet this set of trusted root certificates is usually provided by default by the host platform.
Such a set typically includes many root certificates from well-known certificate authorities like
Entrust and Verisign.

R8 / ProGuard
-------------

R8 and ProGuard are both code optimizers for `.class` files.

R8 is the [default optimizer][r8] in Android Studio 3.4 and newer. It works well with all
releases of OkHttp.

ProGuard was the previous default. We’re [tracking problems][proguard_problems] with interactions
between ProGuard, OkHttp 4.x, and Kotlin-originated `.class` files. Make sure you’re on the latest

 * it easy to get sample values to use in such tests.
 *
 * This class is pretty fast and loose with default values: it attempts to provide values that are
 * well-formed, but doesn't guarantee values are internally consistent. Callers must take care to
 * configure the factory when sample values impact the correctness of the test.
 */
class TestValueFactory : Closeable {

     * were added by default.
     */
    fun clearHeaders() =
      apply {
        headers = Headers.Builder()
      }

    /**
     * Adds [header] as an HTTP header. For well-formed HTTP [header] should contain a name followed
     * by a colon and a value.
     */
    fun addHeader(header: String) =
      apply {
        headers.add(header)
      }

    /**