*  Breaking: Use `kotlin.time.Duration` in APIs like `OkHttpClient.Builder.callTimeout()`. This
    update also drops support for the `DurationUnit` functions introduced in earlier alpha releases
    of OkHttp 5.

 *  Breaking: Reorder the parameters in the Cache constructor that was introduced in 5.0.0-alpha.3.

 *  New: `Request.Builder.cacheUrlOverride()` customizes the cache key used for a request. This can

    This regression was introduced in OkHttp 4.3.0.
 *  Fix: Don't crash with an `IllegalArgumentException` when using custom trust managers on
    Android 10. Android uses reflection to look up a magic `checkServerTrusted()` method and we
    didn't have it.
 *  Fix: Explicitly specify the remote server name when making HTTPS connections on Android 5. In

   */
  public static final String CONTENT_SECURITY_POLICY_REPORT_ONLY =
      "Content-Security-Policy-Report-Only";

  /**
   * The HTTP nonstandard {@code X-Content-Security-Policy} header field name. It was introduced in
   * <a href="https://www.w3.org/TR/2011/WD-CSP-20111129/">CSP v.1</a> and used by the Firefox until
   * version 23 and the Internet Explorer version 10. Please, use {@link #CONTENT_SECURITY_POLICY}
   * to pass the CSP.

release if you’re using ProGuard,


Gradle
------

OkHttp 4’s minimum requirements are Java 8+ and Android 5+. These requirements were
[first introduced][require_android_5] with OkHttp 3.13.

Here’s what you need in `build.gradle` to target Java 8 byte code for Kotlin, Java, and Android
plugins respectively.

```groovy
compileKotlin {
  kotlinOptions {

     * security. ECDSA keys are noticeably faster than RSA keys.
     *
     * This is the default configuration and has been since this API was introduced in OkHttp
     * 3.11.0. Note that the default may change in future releases.
     */
    fun ecdsa256() =
      apply {
        keyAlgorithm = "EC"
        keySize = 256
      }

    /**

    return typeVariable;
  }

  /**
   * Invocation handler to work around a compatibility problem between Android and Java.
   *
   * <p>Java 8 introduced a new method {@code getAnnotatedBounds()} in the {@link TypeVariable}
   * interface, whose return type {@code AnnotatedType[]} is also new in Java 8. As of 2025, Android

  * New SchedulerExtender enables users to implement custom
out-of-(the-scheduler)-process scheduling predicates and priority functions,
for example to schedule pods based on resources that are not directly managed

    return typeVariable;
  }

  /**
   * Invocation handler to work around a compatibility problem between Android and Java.
   *
   * <p>Java 8 introduced a new method {@code getAnnotatedBounds()} in the {@link TypeVariable}
   * interface, whose return type {@code AnnotatedType[]} is also new in Java 8. As of 2025, Android

   *     JDK 8 and on all Android versions. Use {@link Throwable#getStackTrace()} directly, or where
   *     possible use the {@code java.lang.StackWalker.walk} method introduced in JDK 9.
   */
  @Deprecated
  @J2ktIncompatible
  @GwtIncompatible // lazyStackTraceIsLazy, jlaStackTrace
  public static List<StackTraceElement> lazyStackTrace(Throwable throwable) {

## Version 2.7.4

_2016-02-07_

 *  Fix: Don't crash when finding the trust manager if the Play Services (GMS)
    security provider is installed.
 *  Fix: The previous release introduced a performance regression on Android,
    caused by looking up CA certificates. This is now fixed.


## Version 2.7.3

_2016-02-06_

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