assertThat(pool.connectionCount()).isEqualTo(1)
  }

  private fun setPolicy(
    pool: RealConnectionPool,
    address: Address,
    policy: ConnectionPool.AddressPolicy,
  ) {
    pool.setPolicy(address, policy)
    taskFaker.runTasks()
  }

  private fun evictAllConnections(pool: RealConnectionPool) {
    pool.evictAll()
    assertThat(pool.connectionCount()).isEqualTo(0)

    return references.size
  }

  /**
   * Adds or replaces the policy for [address].
   * This will trigger a background task to start creating connections as needed.
   */
  fun setPolicy(
    address: Address,
    policy: ConnectionPool.AddressPolicy,
  ) {
    val state = AddressState(address, taskRunner.newQueue(), policy)
    val newConnectionsNeeded: Int

    while (true) {

        writeHttpResponse(socket, sink, response)
      }

      var hasBody = false
      val policy = dispatcher.peek()
      val requestBodySink =
        requestBody.withThrottlingAndSocketPolicy(
          policy = policy,
          disconnectHalfway = policy.socketPolicy == DisconnectDuringRequestBody,
          expectedByteCount = contentLength,
          socket = socket,
        ).buffer()

      }

    /** Sets the trailers and returns this. */
    fun trailers(trailers: Headers) =
      apply {
        this.trailers = trailers.newBuilder()
      }

    /** Sets the socket policy and returns this. */
    fun socketPolicy(socketPolicy: SocketPolicy) =
      apply {
        this.socketPolicy = socketPolicy
      }

    /**

import okhttp3.internal.commonOnlyIfCached
import okhttp3.internal.commonParse
import okhttp3.internal.commonToString

/**
 * A Cache-Control header with cache directives from a server or client. These directives set policy
 * on what responses can be stored, and which requests can be satisfied by those stored responses.
 *
 * See [RFC 7234, 5.2](https://tools.ietf.org/html/rfc7234#section-5.2).
 */
class CacheControl internal constructor(

      val host = route.address.url.host
      if (!Platform.get().isCleartextTrafficPermitted(host)) {
        throw UnknownServiceException(
          "CLEARTEXT communication to $host not permitted by network security policy",
        )
      }
    } else {
      if (Protocol.H2_PRIOR_KNOWLEDGE in route.address.protocols) {
        throw UnknownServiceException("H2_PRIOR_KNOWLEDGE cannot be used with HTTPS")
      }
    }

These loosely follow the model set in [Google Cloud Policies](https://cloud.google.com/load-balancing/docs/ssl-policies-concepts). We [track changes](../security/tls_configuration_history.md) to this policy.

By default, OkHttp will attempt a `MODERN_TLS` connection.  However by configuring the client connectionSpecs you can allow a fall back to `COMPATIBLE_TLS` connection if the modern configuration fails.

```java

 *  New: `ConnectionPool.setPolicy()` configures a minimum connection pool size for a target
    address. Use this to proactively open HTTP connections.

    Connections opened to fulfill this policy are subject to the connection pool's
    `keepAliveDuration` but do not count against the pool-wide `maxIdleConnections` limit.

    This feature increases the client's traffic and the load on the server. Talking to your server's

    dropped these cipher suite.

## Version 2.5.0

_2015-08-25_

 *  **Timeouts now default to 10 seconds.** Previously we defaulted to never
    timing out, and that was a lousy policy. If establishing a connection,
    reading the next byte from a connection, or writing the next byte to a
    connection takes more than 10 seconds to complete, you’ll need to adjust
    the timeouts manually.

 * SSL socket. For example, if an SSL socket does not have TLS 1.3 enabled, it will not be used even
 * if it is present on the connection spec. The same policy also applies to cipher suites.
 *
 * Use [Builder.allEnabledTlsVersions] and [Builder.allEnabledCipherSuites] to defer all feature
 * selection to the underlying SSL socket.
 *