* suitable for testing that map entries cannot be modified via a nefarious implementation of
   * equals. This is used for testing unmodifiable collections of map entries; for example, it
   * should not be possible to access the raw (modifiable) map entry via a nefarious equals method.
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>
      Entry<K, V> nefariousMapEntry(K key, V value) {

   *
   * <pre>
   * Iterables.filter(Throwables.getCausalChain(e), IOException.class));
   * </pre>
   *
   * @param throwable the non-null {@code Throwable} to extract causes from
   * @return an unmodifiable list containing the cause chain starting with {@code throwable}
   * @throws IllegalArgumentException if there is a loop in the causal chain
   */
  public static List<Throwable> getCausalChain(Throwable throwable) {

      this.entrySplitter = checkNotNull(entrySplitter);
    }

    /**
     * Splits {@code sequence} into substrings, splits each substring into an entry, and returns an
     * unmodifiable map with each of the entries. For example, {@code
     * Splitter.on(';').trimResults().withKeyValueSeparator("=>").split("a=>b ; c=>b")} will return
     * a mapping from {@code "a"} to {@code "b"} and {@code "c"} to {@code "b"}.

   *
   * <pre>
   * Iterables.filter(Throwables.getCausalChain(e), IOException.class));
   * </pre>
   *
   * @param throwable the non-null {@code Throwable} to extract causes from
   * @return an unmodifiable list containing the cause chain starting with {@code throwable}
   * @throws IllegalArgumentException if there is a loop in the causal chain
   */
  public static List<Throwable> getCausalChain(Throwable throwable) {

 * }
 *
 * <p>Instances of {@link ImmutableNetwork} do not implement {@link MutableNetwork} (obviously!) and
 * are contractually guaranteed to be unmodifiable and thread-safe.
 *
 * <p>The Guava User Guide has <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#building-graph-instances">more
 * information on (and examples of) building graphs</a>.
 *

   * its entry set handles modifications.
   *
   * @return a set of entries representing the data of this multiset
   */
  Set<Entry<E>> entrySet();

  /**
   * An unmodifiable element-count pair for a multiset. The {@link Multiset#entrySet} method returns
   * a view of the multiset whose elements are of this class. A multiset implementation may return

      this.entrySplitter = checkNotNull(entrySplitter);
    }

    /**
     * Splits {@code sequence} into substrings, splits each substring into an entry, and returns an
     * unmodifiable map with each of the entries. For example, {@code
     * Splitter.on(';').trimResults().withKeyValueSeparator("=>").split("a=>b ; c=>b")} will return
     * a mapping from {@code "a"} to {@code "b"} and {@code "c"} to {@code "b"}.

   * its entry set handles modifications.
   *
   * @return a set of entries representing the data of this multiset
   */
  Set<Entry<E>> entrySet();

  /**
   * An unmodifiable element-count pair for a multiset. The {@link Multiset#entrySet} method returns
   * a view of the multiset whose elements are of this class. A multiset implementation may return

 */
package okhttp3

import java.nio.charset.Charset
import java.util.Collections.singletonMap
import java.util.Locale.US
import kotlin.text.Charsets.ISO_8859_1
import okhttp3.internal.unmodifiable

/**
 * An [RFC 7235][rfc_7235] challenge.
 *
 * [rfc_7235]: https://tools.ietf.org/html/rfc7235
 */
class Challenge(
  /** Returns the authentication scheme, like `Basic`. */

        if (protocolsCopy != this.protocols) {
          this.routeDatabase = null
        }

        // Assign as an unmodifiable list. This is effectively immutable.
        this.protocols = protocolsCopy.unmodifiable()
      }

    /**
     * Sets the verifier used to confirm that response certificates apply to requested hostnames for
     * HTTPS connections.
     *