* 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.
 *

        .clearHeaders()
        .code(HttpURLConnection.HTTP_NOT_MODIFIED)
        .addHeader("Content-Encoding: gzip")
        .build(),
    )
    server.enqueue(
      MockResponse(body = "b"),
    )
    val response1 = getResponse(newRequest("/"))
    assertThat(response1.code).isEqualTo(HttpURLConnection.HTTP_NOT_MODIFIED)
    assertContent("", response1)

 * limitations under the License.
 */
@file:JvmName("HttpHeaders")

package okhttp3.internal.http

import java.io.EOFException
import java.net.HttpURLConnection.HTTP_NOT_MODIFIED
import java.net.HttpURLConnection.HTTP_NO_CONTENT
import java.util.Collections
import okhttp3.Challenge
import okhttp3.Cookie
import okhttp3.CookieJar
import okhttp3.Headers
import okhttp3.HttpUrl

          ?: throw ProtocolException(
            "Unexpected status line: $statusLine",
          )

      // Parse an optional response message like "OK" or "Not Modified". If it
      // exists, it is separated from the response code by a space.
      var message = ""
      if (statusLine.length > codeStart + 3) {
        if (statusLine[codeStart + 3] != ' ') {

 * the response, the client will issue a conditional `GET`. The server will then send either
 * the updated response if it has changed, or a short 'not modified' response if the client's copy
 * is still valid. Such responses increment both the network count and hit count.
 *
 * The best way to improve the cache hit rate is by configuring the web server to return cacheable

          ),
        body = "A",
      ),
    )
    server.enqueue(
      MockResponse.Builder()
        .clearHeaders()
        .addHeader("Donut: b")
        .code(HttpURLConnection.HTTP_NOT_MODIFIED)
        .build(),
    )
    client =
      client.newBuilder()
        .cache(cache)
        .build()

    // Store a response in the cache.

        headers =
          headersOf(
            "Last-Modified",
            formatDate(-1, TimeUnit.HOURS)!!,
            "Expires",
            formatDate(1, TimeUnit.HOURS)!!,
          ),
        body = "ABC.1",
      ),
    )
    server.enqueue(
      MockResponse(
        headers =
          headersOf(
            "Last-Modified",
            formatDate(-1, TimeUnit.HOURS)!!,

 *  limitations under the License.
 */
package okhttp3.internal.cache

import java.io.IOException
import java.net.HttpURLConnection.HTTP_GATEWAY_TIMEOUT
import java.net.HttpURLConnection.HTTP_NOT_MODIFIED
import java.util.concurrent.TimeUnit.MILLISECONDS
import okhttp3.Cache
import okhttp3.EventListener
import okhttp3.Headers
import okhttp3.Interceptor
import okhttp3.Protocol
import okhttp3.Request

in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: (a) You must give any other recipients of the Work or Derivative Works a copy of this License; and (b) You must cause any modified files to carry prominent notices stating that You changed the files; and (c) You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work,...

    server.enqueue(
      MockResponse(
        headers = headersOf("ETag", "v1"),
        body = "A",
      ),
    )
    server.enqueue(
      MockResponse(code = HttpURLConnection.HTTP_NOT_MODIFIED),
    )
    val call1 = client.newCall(Request(server.url("/")))
    val response1 = call1.execute()
    assertThat(response1.body.string()).isEqualTo("A")
    assertThat(cache.requestCount()).isEqualTo(1)