*   }
 * ```
 */
fun interface Interceptor {
  @Throws(IOException::class)
  fun intercept(chain: Chain): Response

  companion object {
    /**
     * Constructs an interceptor for a lambda. This compact syntax is most useful for inline
     * interceptors.
     *
     * ```kotlin
     * val interceptor = Interceptor { chain: Interceptor.Chain ->
     *     chain.proceed(chain.request())
     * }

	public fun intercept (Lokhttp3/Interceptor$Chain;)Lokhttp3/Response;
	public final fun level (Lokhttp3/logging/HttpLoggingInterceptor$Level;)V
	public final fun redactHeader (Ljava/lang/String;)V
	public final fun redactQueryParams ([Ljava/lang/String;)V
	public final fun setLevel (Lokhttp3/logging/HttpLoggingInterceptor$Level;)Lokhttp3/logging/HttpLoggingInterceptor;
}

![Interceptors Diagram](../assets/images/interceptors@2x.png)

### Application Interceptors

Interceptors are registered as either _application_ or _network_ interceptors. We'll use the `LoggingInterceptor` defined above to show the difference.

Register an _application_ interceptor by calling `addInterceptor()` on `OkHttpClient.Builder`:

      assertThat(expected.message).isEqualTo(
        "network interceptor $interceptor must call proceed() exactly once",
      )
    }
  }

  @Test
  fun networkInterceptorsCannotChangeServerAddress() {
    server.enqueue(
      MockResponse.Builder()
        .code(500)
        .build(),
    )
    val interceptor =
      Interceptor { chain: Interceptor.Chain ->

    // Call the next interceptor in the chain.
    val next = copy(index = index + 1, request = request)
    val interceptor = interceptors[index]

    @Suppress("USELESS_ELVIS")
    val response =
      interceptor.intercept(next) ?: throw NullPointerException(
        "interceptor $interceptor returned null",
      )

    if (exchange != null) {
      check(index + 1 >= interceptors.size || next.calls == 1) {

import java.net.ProtocolException
import okhttp3.Interceptor
import okhttp3.Response
import okhttp3.internal.connection.Exchange
import okhttp3.internal.http2.ConnectionShutdownException
import okhttp3.internal.stripBody
import okio.buffer

/** This is the last interceptor in the chain. It makes a network call to the server. */
class CallServerInterceptor(private val forWebSocket: Boolean) : Interceptor {
  @Throws(IOException::class)

 */
package okhttp3.brotli

import okhttp3.Interceptor
import okhttp3.Response
import okhttp3.brotli.internal.uncompress

/**
 * Transparent Brotli response support.
 *
 * Adds Accept-Encoding: br to request and checks (and strips) for Content-Encoding: br in
 * responses.  n.b. this replaces the transparent gzip compression in BridgeInterceptor.
 */
object BrotliInterceptor : Interceptor {

 *
 * The format of the logs created by this class should not be considered stable and may
 * change slightly between releases. If you need a stable logging format, use your own interceptor.
 */
class HttpLoggingInterceptor
  @JvmOverloads
  constructor(
    private val logger: Logger = Logger.DEFAULT,
  ) : Interceptor {

import okhttp3.internal.withSuppressed

/**
 * This interceptor recovers from failures and follows redirects as necessary. It may throw an
 * [IOException] if the call was canceled.
 */
class RetryAndFollowUpInterceptor(private val client: OkHttpClient) : Interceptor {
  @Throws(IOException::class)
  override fun intercept(chain: Interceptor.Chain): Response {
    val realChain = chain as RealInterceptorChain

Logging Interceptor
===================

An [OkHttp interceptor][interceptors] which logs HTTP request and response data.

```java
HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
logging.setLevel(Level.BASIC);
OkHttpClient client = new OkHttpClient.Builder()
  .addInterceptor(logging)
  .build();
```

You can change the log level at any time by calling `setLevel()`.