/**
   * Segments are specialized versions of hash tables. This subclass inherits from ReentrantLock
   * opportunistically, just to simplify some locking and avoid separate construction.
   */
  @SuppressWarnings("serial") // This class is never serialized.
  abstract static class Segment<
          K, V, E extends InternalEntry<K, V, E>, S extends Segment<K, V, E, S>>
      extends ReentrantLock {

    /*

### Step 1: Ensure Elasticsearch minimum requirements are met

MinIO requires a 5.x series version of Elasticsearch. This is the latest major release series. Elasticsearch provides version upgrade migration guidelines [here](https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-upgrade.html).

### Step 2: Add Elasticsearch endpoint to MinIO

  }

  /** Implementation of {@link #whitespace()}. */
  @VisibleForTesting
  static final class Whitespace extends NamedFastMatcher {

    // TABLE is a precomputed hashset of whitespace characters. MULTIPLIER serves as a hash function
    // whose key property is that it maps 25 characters into the 32-slot table without collision.
    // Basically this is an opportunistic fast implementation as opposed to "good code". For most

   * more convenient.
   *
   * <p>Builder instances can be reused - it is safe to call {@link #buildOrThrow} multiple times to
   * build multiple maps in series. Each map is a superset of the maps created before it.
   *
   * @since 2.0
   */
  public static class Builder<K, V> extends ImmutableMap.Builder<K, V> {
    private transient @Nullable Object[] keys;

    }

    private static final long serialVersionUID = 0;
  }

  /**
   * Returns a synchronized (thread-safe) navigable set backed by the specified navigable set. In
   * order to guarantee serial access, it is critical that <b>all</b> access to the backing
   * navigable set is accomplished through the returned navigable set (or its views).
   *

 *  New: `Challenge` includes all authentication parameters.
 *  New: Upgrade to BouncyCastle 1.60, Conscrypt 1.4.0, and Okio 1.15.0. We don't yet require
    Kotlin-friendly Okio 2.x but OkHttp works fine with that series.

    ```kotlin
    implementation("org.bouncycastle:bcprov-jdk15on:1.60")
    implementation("org.conscrypt:conscrypt-openjdk-uber:1.4.0")
    implementation("com.squareup.okio:okio:1.15.0")
    ```

      dest.put(entry.getValue(), entry.getKey());
    }
    return dest;
  }

  /**
   * Returns a synchronized (thread-safe) multimap backed by the specified multimap. In order to
   * guarantee serial access, it is critical that <b>all</b> access to the backing multimap is
   * accomplished through the returned multimap.
   *
   * <p>It is imperative that the user manually synchronize on the returned multimap when accessing