* your HTTP calls. This is because each client holds its own connection pool and thread pools.
 * Reusing connections and threads reduces latency and saves memory. Conversely, creating a client
 * for each request wastes resources on idle pools.
 *
 * Use `new OkHttpClient()` to create a shared instance with the default settings:
 *
 * ```java
 * // The singleton HTTP client.

    /** Gets the key for this entry. */
    K getKey();

    /** Gets the value for the entry. */
    V getValue();
  }

  /*
   * Note: the following classes have a lot of duplicate code. It sucks, but it saves a lot of
   * memory. If only Java had mixins!
   */

  /** Base class for {@link InternalEntry} implementations for strong keys. */
  abstract static class AbstractStrongKeyEntry<K, V, E extends InternalEntry<K, V, E>>