Interceptors can be chained. Suppose you have both a compressing interceptor and a checksumming interceptor: you'll need to decide whether data is compressed and then checksummed, or checksummed and then compressed. OkHttp uses lists to track interceptors, and interceptors are called in order.

![Interceptors Diagram](../assets/images/******@****.***)

_2016-02-06_

 *  Fix: Permit the trusted CA root to be pinned by `CertificatePinner`.


## Version 2.7.2

_2016-01-07_

 *  Fix: Don't eagerly release stream allocations on cache hits. We might still
    need them to handle redirects.


## Version 2.7.1

_2016-01-01_

 *  Fix: Don't do a health check on newly-created connections. This is
    unnecessary work that could put the client in an inconsistent state if the

          Log.println(logLevel, tag, logMessage.substring(i, end))
          i = end
        } while (i < newline)
        i++
      }
    }
  }

  private fun loggerTag(loggerName: String): String {
    // We need to handle long logger names before they hit Log.
    // java.lang.IllegalArgumentException: Log tag "okhttp3.mockwebserver.MockWebServer" exceeds limit of 23 characters
    return knownLoggers[loggerName] ?: loggerName.take(23)
  }

 * [event listener factory][OkHttpClient.eventListenerFactory].
 *
 * The format of the logs created by this class should not be considered stable and may change
 * slightly between releases. If you need a stable logging format, use your own event listener.
 */
class LoggingEventListener private constructor(
  private val logger: HttpLoggingInterceptor.Logger,
) : EventListener() {
  private var startNs: Long = 0

   */
  fun hasNext(failedConnection: RealConnection? = null): Boolean

  /**
   * Returns true if the host and port are unchanged from when this was created. This is used to
   * detect if followups need to do a full connection-finding process including DNS resolution, and
   * certificate pin checks.
   */
  fun sameHostAndPort(url: HttpUrl): Boolean

  /**

#

##############################################################################
#
#   Gradle start up script for POSIX generated by Gradle.
#
#   Important for running:
#
#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
#       noncompliant, but you have some other compliant shell such as ksh or
#       bash, then to run this script, type that shell name before the whole

:end
@rem End local scope for the variables with windows NT shell
if %ERRORLEVEL% equ 0 goto mainEnd

:fail
rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
rem the _cmd.exe /c_ return code!
set EXIT_CODE=%ERRORLEVEL%
if %EXIT_CODE% equ 0 set EXIT_CODE=1
if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
exit /b %EXIT_CODE%

:mainEnd

  // performed while holding this lock!
  //
  // Socket writes are guarded by frameWriter.
  //
  // Socket reads are unguarded but are only made by the reader thread.
  //
  // Certain operations (like SYN_STREAM) need to synchronize on both the frameWriter (to do
  // blocking I/O) and this (to create streams). Such operations must synchronize on 'this' last.
  // This ensures that we never wait for a blocking operation while holding 'this'.

    assertThat(dnsEnd.inetAddressList.size).isEqualTo(1)
  }

  @Test
  fun noDnsLookupOnPooledConnection() {
    server.enqueue(MockResponse())
    server.enqueue(MockResponse())

    // Seed the pool.
    val call1 =
      client.newCall(
        Request.Builder()
          .url(server.url("/"))
          .build(),
      )
    val response1 = call1.execute()

      }
    }

  companion object {
    /**
     * The "mixed" subtype of "multipart" is intended for use when the body parts are independent
     * and need to be bundled in a particular order. Any "multipart" subtypes that an implementation
     * does not recognize must be treated as being of subtype "mixed".
     */
    @JvmField
    val MIXED = "multipart/mixed".toMediaType()