.isEqualTo("20990101000000Z")
  }

  @Test fun `decode object identifier`() {
    val bytes = "06092a864886f70d01010b".decodeHex()
    assertThat(Adapters.OBJECT_IDENTIFIER.fromDer(bytes)).isEqualTo(SHA256_WITH_RSA_ENCRYPTION)
    assertThat(Adapters.OBJECT_IDENTIFIER.toDer(SHA256_WITH_RSA_ENCRYPTION)).isEqualTo(bytes)
  }

  @Test fun `null value`() {

        ObjectIdentifiers.RSA_ENCRYPTION -> Adapters.NULL
        ObjectIdentifiers.EC_PUBLIC_KEY -> Adapters.OBJECT_IDENTIFIER
        else -> null
      }
    }

  /**
   * ```
   * AlgorithmIdentifier ::= SEQUENCE  {
   *   algorithm      OBJECT IDENTIFIER,
   *   parameters     ANY DEFINED BY algorithm OPTIONAL
   * }
   * ```
   */

          override fun encode(
            writer: DerWriter,
            value: Unit?,
          ) {
          }
        },
    )

  val OBJECT_IDENTIFIER =
    BasicDerAdapter(
      name = "OBJECT IDENTIFIER",
      tagClass = DerHeader.TAG_CLASS_UNIVERSAL,
      tag = 6L,
      codec =
        object : BasicDerAdapter.Codec<String> {

    assertThat(cs.hashCode(), cs.toString())
      .isEqualTo(System.identityHashCode(cs))
  }

  @Test
  fun hashCode_usesIdentityHashCode_regularCase() {
    // This one's javaName matches the identifier.
    val cs = CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA256
    assertThat(cs.hashCode(), cs.toString())
      .isEqualTo(System.identityHashCode(cs))
  }

  @Test
  fun instancesAreInterned() {

import okio.ByteString.Companion.toByteString

/**
 * A certificate and its private key. These are some properties of certificates that are used with
 * TLS:
 *
 *  * **A common name.** This is a string identifier for the certificate. It usually describes the
 *    purpose of the certificate like "Entrust Root Certification Authority - G2" or
 *    "www.squareup.com".
 *

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

/** ASN.1 object identifiers used internally by this implementation. */
internal object ObjectIdentifiers {
  const val EC_PUBLIC_KEY = "1.2.840.10045.2.1"
  const val SHA256_WITH_ECDSA = "1.2.840.10045.4.3.2"

    // +---------------+---------------+---------------+
    // |   Type (8)    |   Flags (8)   |
    // +-+-+-----------+---------------+-------------------------------+
    // |R|                 Stream Identifier (31)                      |
    // +=+=============================================================+
    // |                   Frame Payload (0...)                      ...

   *
   * [iana]: https://www.iana.org/assignments/tls-extensiontype-values
   */
  override fun toString(): String = protocol

  companion object {
    /**
     * Returns the protocol identified by `protocol`.
     *
     * @throws IOException if `protocol` is unknown.
     */
    @JvmStatic
    @Throws(IOException::class)
    fun get(protocol: String): Protocol {

    /**
     * @param javaName the name used by Java APIs for this cipher suite. Different than the IANA
     *     name for older cipher suites because the prefix is `SSL_` instead of `TLS_`.
     * @param value the integer identifier for this cipher suite. (Documentation only.)
     */
    private fun init(
      javaName: String,
      value: Int,
    ): CipherSuite {
      val suite = CipherSuite(javaName)

 * They don't specify whether a specific proxy server should be used or how to authenticate with that proxy server.

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/)