// OkHttp 2.x:
    HttpURLConnection connection = new OkUrlFactory(client).open(url);
    ```

 *  **Custom caches are no longer supported.** In OkHttp 1.x it was possible to
    define your own response cache with the `java.net.ResponseCache` and OkHttp's
    `OkResponseCache` interfaces. Both of these APIs have been dropped. In
    OkHttp 2 the built-in disk cache is the only supported response cache.

     *     .sslSocketFactory(sslSocketFactory, trustManager)
     *     .build();
     * ```
     *
     * ## TrustManagers on Android are Weird!
     *
     * Trust managers targeting Android must also define a method that has this signature:
     *
     * ```java
     *    @SuppressWarnings("unused")
     *    public List<X509Certificate> checkServerTrusted(

 *
 * Each entry is 4 bytes, and represents a _range_ of code points that all share a common 14-bit
 * prefix. Entries are sorted by their complete code points.
 *
 * The 4 bytes are named b0, b1, b2 and b3. We also define these supplemental values:
 *
 *  * **b2a**: b2 + 0x80
 *  * **b3a**: b3 + 0x80
 *  * **b2b3**: (b2 << 7) + b3
 *
 * b0
 * --
 *

    val receiveBuffer = Buffer()

    /** Buffer with readable data. Guarded by Http2Stream.this. */
    val readBuffer = Buffer()

    /**
     * Received trailers. Null unless the server has provided trailers. Undefined until the stream
     * is exhausted. Guarded by Http2Stream.this.
     */
    var trailers: Headers? = null

    /** True if the caller has closed this stream. */
    internal var closed: Boolean = false

    .addSubjectAlternativeName("localhost")
    .build();
```

[`HandshakeCertificates`][handshake_certificates] keeps the certificates for a TLS handshake.
Use its [builder][handshake_certificates_builder] to define which certificates the HTTPS server
returns to its clients. The returned instance can create an `SSLSocketFactory` that implements this
policy:

```java

    } catch (_: IllegalArgumentException) {
      defaultValue // This charset is invalid or unsupported. Give up.
    }
  }

  /**
   * Returns the parameter [name] of this media type, or null if this media type does not define
   * such a parameter.
   */
  fun parameter(name: String): String? = commonParameter(name)

  @JvmName("-deprecated_type")
  @Deprecated(
    message = "moved to val",

SAM Conversions
---------------

When you use Java APIs from Kotlin you can operate on Java interfaces as if they were Kotlin
lambdas. The [feature][java_sams] is available for interfaces that define a Single Abstract Method
(SAM).

But when you use Kotlin APIs from Kotlin there’s no automatic conversion. Code that used SAM lambdas
with OkHttp 3.x: must use `object :` with OkHttp 4.x:

Kotlin calling OkHttp 3.x:

`MultipartBody.Builder` can build sophisticated request bodies compatible with HTML file upload forms. Each part of a multipart request body is itself a request body, and can define its own headers. If present, these headers should describe the part body, such as its `Content-Disposition`. The `Content-Length` and `Content-Type` headers are added automatically if they're available.