* to determine the charset of the response bytes.
   *
   * Otherwise the response bytes are decoded as UTF-8.
   */
  fun charStream(): Reader =
    reader ?: BomAwareReader(source(), charset()).also {
      reader = it
    }

  /**
   * Returns the response as a string.
   *
   * If the response starts with a

import okhttp3.internal.toImmutableList
import okhttp3.tls.internal.TlsUtil.newKeyManager
import okhttp3.tls.internal.TlsUtil.newTrustManager

/**
 * Certificates to identify which peers to trust and also to earn the trust of those peers in kind.
 * Client and server exchange these certificates during the handshake phase of a TLS connection.
 *
 * ### Server Authentication
 *

    // UTF-16LE.
    "fffe".decodeHex(),
    // UTF-32BE.
    "0000ffff".decodeHex(),
    // UTF-32LE.
    "ffff0000".decodeHex(),
  )

/**
 * Returns an array containing only elements found in this array and also in [other]. The returned
 * elements are in the same order as in this.
 */
internal fun Array<String>.intersect(
  other: Array<String>,
  comparator: Comparator<in String>,
): Array<String> {

      builder.build()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Null interceptor: [null]")
    }
  }

  @Test fun nullNetworkInterceptorInList() {
    val builder = OkHttpClient.Builder()
    builder.networkInterceptors().addAll(listOf(null) as List<Interceptor>)
    assertFailsWith<IllegalStateException> {
      builder.build()
    }.also { expected ->

        .build()
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("At least one TLS version is required")
    }
  }

  @Test
  fun noCipherSuites() {
    assertFailsWith<IllegalArgumentException> {
      ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
        .cipherSuites(*arrayOf<CipherSuite>())
        .build()
    }.also { expected ->
      assertThat(expected.message)

## [Requests](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-request/)

Each HTTP request contains a URL, a method (like `GET` or `POST`), and a list of headers. Requests may also contain a body: a data stream of a specific content type.

## [Responses](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-response/)

        .addTrustedCertificate(entrustRootCertificateAuthority)
        .addTrustedCertificate(comodoRsaCertificationAuthority)
        // Uncomment if standard certificates are also required.
        // .addPlatformTrustedCertificates()
        .build()
    client =
      OkHttpClient.Builder()
        .sslSocketFactory(certificates.sslSocketFactory(), certificates.trustManager)
        .build()

  /** Returns an immutable list of the header values for `name`. */
  fun values(name: String): List<String> = commonValues(name)

  /**
   * Returns the number of bytes required to encode these headers using HTTP/1.1. This is also the
   * approximate size of HTTP/2 headers before they are compressed with HPACK. This value is
   * intended to be used as a metric: smaller headers are more efficient to encode and transmit.
   */
  fun byteCount(): Long {

      Headers.Builder()
        .add("foo: bar")
        .add(" foo: baz") // Name leading whitespace is trimmed.
        .add("foo : bak") // Name trailing whitespace is trimmed.
        .add("\tkey\t:\tvalue\t") // '\t' also counts as whitespace
        .add("ping:  pong  ") // Value whitespace is trimmed.
        .add("kit:kat") // Space after colon is not required.
        .build()

import okhttp3.internal.immutableListOf
import okhttp3.internal.toImmutableList

/**
 * Selects routes to connect to an origin server. Each connection requires a choice of proxy server,
 * IP address, and TLS mode. Connections may also be recycled.
 */
class RouteSelector(
  private val address: Address,
  private val routeDatabase: RouteDatabase,
  private val connectionUser: ConnectionUser,
  private val fastFallback: Boolean,
) {