/**
     * Channel binding is disabled
     */
    public static final int CHANNEL_BINDING_DISABLED = 0;

    /**
     * Channel binding is preferred but not required
     */
    public static final int CHANNEL_BINDING_PREFERRED = 1;

    /**
     * Channel binding is required
     */
    public static final int CHANNEL_BINDING_REQUIRED = 2;

    /**

 * used so that OkHttp can learn from its mistakes: if there was a failure attempting to connect to
 * a specific IP address or proxy server, that failure is remembered and alternate routes are
 * preferred.
 */
class RouteDatabase {
  private val _failedRoutes = mutableSetOf<Route>()

  val failedRoutes: Set<Route>
    @Synchronized get() = _failedRoutes.toSet()

 * guaranteed to be supported by all Java platform implementations.
 *
 * <p>Assuming you're free to choose, note that <b>{@link #UTF_8} is widely preferred</b>.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/StringsExplained#charsets">{@code Charsets}</a>.
 *
 * @author Mike Bostock
 * @since 1.0
 */
@GwtCompatible

 * guaranteed to be supported by all Java platform implementations.
 *
 * <p>Assuming you're free to choose, note that <b>{@link #UTF_8} is widely preferred</b>.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/StringsExplained#charsets">{@code Charsets}</a>.
 *
 * @author Mike Bostock
 * @since 1.0
 */
@GwtCompatible

  //  - Some providers may choose to also include alias names.
  //  - For example, the "SHA-1" algorithm might be referred to as "SHA1".
  //  - The algorithm name is not case-sensitive.
  @SuppressWarnings("deprecation") // We still need to test our deprecated APIs.
  private static final ImmutableMap<String, HashFunction> ALGORITHMS =

 but is ready to use other logging implementations: SLF4J is responsible for loading the implementation, referred to as
 {{{http://www.slf4j.org/manual.html#swapping}"SLF4J bindings"}}.

 Logging configuration loading is actually done by logging implementation, without any Maven extensions to support merging

   * there's no way to assign a {@code @Nullable T} to a field {@code T foo;} and instruct the
   * analysis that that means "plain {@code T}" rather than the inferred type {@code @Nullable T}.
   * (And even if annotations on local variables were permitted as an optional hint, no annotation
   * would be the right tool for the job here: {@code @Nullable} is the annotation that we're trying

   * there's no way to assign a {@code @Nullable T} to a field {@code T foo;} and instruct the
   * analysis that that means "plain {@code T}" rather than the inferred type {@code @Nullable T}.
   * (And even if annotations on local variables were permitted as an optional hint, no annotation
   * would be the right tool for the job here: {@code @Nullable} is the annotation that we're trying

        /**
         * Returns the algorithm name, usually used as key, never {@code null} value. The name is a standard name of
         * algorithm (if applicable) or any other designator that is algorithm commonly referred with. Example: "SHA-1".
         */
        @Nonnull
        String getName();

        /**
         * Returns the file extension to be used for given checksum file (without leading dot), never {@code null}. The

 * or resolution request is performed is controlled by the {@link #pathScope()}
 * field, the injected field type and the {@link #requestType()}.
 * <p>
 * If the {@code requestType} is not set explicitly, it will be inferred
 * from the {@code pathScope} and the injected field type. If the type
 * is {@link org.apache.maven.api.Node Node} and {@code pathScope == ""},
 * then the dependencies will be <i>collected</i>.