| [GraalVM]        | ✅      |              | [OpenJDK]       | Only actively tested with JDK 11, not with 8 target          |
| [Bouncy Castle]  | ✅      |              | [Bouncy Castle] | [Tracking bug.][bug5698]                                     |
| [Conscrypt]      | ✅      | ✅           | [BoringSSL]     | Activated if Conscrypt is first registered provider.         |

---


# Recipes

We've written some recipes that demonstrate how to solve common problems with OkHttp. Read through them to learn about how everything works together. Cut-and-paste these examples freely; that's what they're for.

### Synchronous Get ([.kt][SynchronousGetKotlin], [.java][SynchronousGetJava])

Download a file, print its headers, and print its response body as a string.

bus.museum
bushey.museum
cadaques.museum
california.museum
cambridge.museum
can.museum
canada.museum
capebreton.museum
carrier.museum
cartoonart.museum
casadelamoneda.museum
castle.museum
castres.museum
celtic.museum
center.museum
chattanooga.museum
cheltenham.museum
chesapeakebay.museum
chicago.museum
children.museum
childrens.museum
childrensgarden.museum

com caravan carbonia-iglesias.it carboniaiglesias.it cards care career careers cargo.aero carrara-massa.it carraramassa.it carrd.co carrier.museum cars cartoonart.museum casa casacam.net casadelamoneda.museum case caserta.it cash casino casino.hu castle.museum castres.museum cat cat.ax catania.it catanzaro.it catering catering.aero catfood.jp catholic catholic.edu.au caxias.br cb.it cba cbg.ru cbn cbre cbs cc cc.ak.us cc.al.us cc.ar.us cc.as.us cc.az.us cc.ca.us cc.co.us cc.ct.us cc.dc.us cc.de.us...

088F          ; disallowed                             # NA   <reserved-088F>
0890..0891    ; disallowed                             # 14.0 ARABIC POUND MARK ABOVE..ARABIC PIASTRE MARK ABOVE
0892..0897    ; disallowed                             # NA   <reserved-0892>..<reserved-0897>
0898..089F    ; valid                                  # 14.0 ARABIC SMALL HIGH WORD AL-JUZ..ARABIC HALF MADDA OVER MADDA

 *    Note that the private key is not a part of the certificate!
 *
 *  * **A signature issued by another certificate's private key.** This mechanism allows a trusted
 *    third-party to endorse a certificate. Third parties should only endorse certificates once
 *    they've confirmed that the owner of the private key is also the owner of the certificate's
 *    other properties.
 *

Debug Logging
=============

OkHttp has internal APIs to enable debug logging. It uses the `java.util.logging` API which can be
tricky to configure. As a shortcut, you can paste [OkHttpDebugLogging.kt]. Then enable debug logging
for whichever features you need:

```
OkHttpDebugLogging.enableHttp2()
OkHttpDebugLogging.enableTaskRunner()
```

### Activating on Android

```
$ adb shell setprop log.tag.okhttp.Http2 DEBUG

_2019-03-14_

 *  **This release deletes the long-deprecated `OkUrlFactory` and `OkApacheClient` APIs.** These
    facades hide OkHttp's implementation behind another client's API. If you still need this please
    copy and paste [ObsoleteUrlFactory.java][obsolete_url_factory] or
    [ObsoleteApacheClient.java][obsolete_apache_client] into your project.

 *  **OkHttp now supports duplex calls over HTTP/2.** With normal HTTP calls the request must finish

import okio.BufferedSource
import okio.ByteString.Companion.encodeUtf8
import okio.Options

class ServerSentEventReader(
  private val source: BufferedSource,
  private val callback: Callback,
) {
  private var lastId: String? = null

  interface Callback {
    fun onEvent(
      id: String?,
      type: String?,
      data: String,
    )

    fun onRetryChange(timeMs: Long)
  }

  /**

    `NullPointerException: bio == null`.


## Version 4.9.0

_2020-09-11_

**With this release, `okhttp-tls` no longer depends on Bouncy Castle and doesn't install the
Bouncy Castle security provider.** If you still need it, you can do it yourself:

```
Security.addProvider(BouncyCastleProvider())
```

You will also need to configure this dependency:

```