### Choosing between application and network interceptors

Each interceptor chain has relative merits.

**Application interceptors**

 * Don't need to worry about intermediate responses like redirects and retries.
 * Are always invoked once, even if the HTTP response is served from the cache.

      assertNotNull(object);
      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    // this uses #get(key), makes sure an already observed stripe is returned
    for (int i = 0; i < striped.size() * 100; i++) {
      assertTrue(observed.contains(striped.get(new Object())));
    }

    try {
      striped.getAt(-1);

      assertNotNull(object);
      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    // this uses #get(key), makes sure an already observed stripe is returned
    for (int i = 0; i < striped.size() * 100; i++) {
      assertTrue(observed.contains(striped.get(new Object())));
    }

    try {
      striped.getAt(-1);

They're also concrete: each URL identifies a specific path (like `/square/okhttp`) and query (like `?q=sharks&lang=en`). Each webserver hosts many URLs.

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

    }

    /**
     * Checks if `expected` and `observed` are equal when viewed as a set and headers are
     * deduped.
     *
     * TODO: See if duped headers should be preserved on decode and verify.
     */
    private fun assertSetEquals(
      message: String,
      expected: List<Header>,
      observed: List<Header>,
    ) {
      assertThat(LinkedHashSet(observed), message)
        .isEqualTo(LinkedHashSet(expected))

If a conditional GET was successful, responses from the network and cache are merged as directed by the spec.

## Follow-up Requests

When your requested URL has moved, the webserver will return a response code like `302` to indicate the document’s new URL. OkHttp will follow the redirect to retrieve a final response.

  @SuppressLint("NewApi")
  override fun getSelectedProtocol(sslSocket: SSLSocket): String? =
    try {
      // SSLSocket.getApplicationProtocol returns "" if application protocols values will not
      // be used. Observed if you didn't specify SSLParameters.setApplicationProtocols
      when (val protocol = sslSocket.applicationProtocol) {
        null, "" -> null
        else -> protocol
      }

  }

  @SuppressSignatureCheck
  override fun getSelectedProtocol(sslSocket: SSLSocket): String? =
    try {
      // SSLSocket.getApplicationProtocol returns "" if application protocols values will not
      // be used. Observed if you didn't specify SSLParameters.setApplicationProtocols
      when (val protocol = sslSocket.applicationProtocol) {
        null, "" -> null
        else -> protocol
      }

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3

import java.io.IOException
import java.util.concurrent.TimeUnit

/**
 * Observes, modifies, and potentially short-circuits requests going out and the corresponding
 * responses coming back in. Typically interceptors add, remove, or transform headers on the request
 * or response.
 *

      }
    }
  }

  companion object {
    val playProviderFactory: DeferredSocketAdapter.Factory =
      factory("com.google.android.gms.org.conscrypt")

    /**
     * Builds a SocketAdapter from an observed implementation class, by grabbing the Class
     * reference to perform reflection on at runtime.
     *
     * @param actualSSLSocketClass the runtime class of Conscrypt class socket.
     */