# Async Tests { #async-tests }

You have already seen how to test your **FastAPI** applications using the provided `TestClient`. Up to now, you have only seen how to write synchronous tests, without using `async` functions.

      return Collections2.safeContains(collection, element);
    }
    return Iterators.contains(iterable.iterator(), element);
  }

  /**
   * Removes, from an iterable, every element that belongs to the provided collection.
   *
   * <p>This method calls {@link Collection#removeAll} if {@code iterable} is a collection, and
   * {@link Iterators#removeAll} otherwise.
   *

This topic provides commands to set up different configurations of hosts, nodes, and drives. The examples provided here can be used as a starting point for other configurations.

1. [Standalone Deployment](#standalone-deployment)
2. [Distributed Deployment](#distributed-deployment)

 *
 * <dl>
 *   <dt>{@link Multimap}
 *   <dd>A new type, which is similar to {@link java.util.Map}, but may contain multiple entries
 *       with the same key. Some behaviors of {@link Multimap} are left unspecified and are provided
 *       only by the subtypes mentioned below.
 *   <dt>{@link ListMultimap}
 *   <dd>An extension of {@link Multimap} which permits duplicate entries, supports random access of

### Create a custom `GzipRequest` class { #create-a-custom-gziprequest-class }

/// tip

This is a toy example to demonstrate how it works, if you need Gzip support, you can use the provided [`GzipMiddleware`](../advanced/middleware.md#gzipmiddleware){.internal-link target=_blank}.

///

      <artifactId>plexus-sec-dispatcher</artifactId>
    </dependency>

    <dependency>
      <groupId>javax.inject</groupId>
      <artifactId>javax.inject</artifactId>
      <scope>provided</scope>
    </dependency>

    <dependency>
      <groupId>org.junit.jupiter</groupId>
      <artifactId>junit-jupiter-api</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>

  private Multimaps() {}

  /**
   * Returns a {@code Collector} accumulating entries into a {@code Multimap} generated from the
   * specified supplier. The keys and values of the entries are the result of applying the provided
   * mapping functions to the input elements, accumulated in the encounter order of the stream.
   *
   * <p>Example:
   *
   * {@snippet :
   * static final ListMultimap<Character, String> FIRST_LETTER_MULTIMAP =

    }

    /**
     * Returns this clock since timezone adjustments are not supported.
     * <p>
     * This implementation maintains UTC time to ensure monotonic behavior.
     * The provided zone parameter is ignored.
     *
     * @param zone the target timezone (ignored)
     * @return this clock instance
     */
    @Override
    public Clock withZone(ZoneId zone) {

 * behavior of {@link #addAll}, which can lead to unexpected behavior. In this case, you should
 * override {@code addAll} as well, either providing your own implementation, or delegating to the
 * provided {@code standardAddAll} method.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations

    return join(iterable(first, second, rest));
  }

  /**
   * Returns a joiner with the same behavior as this one, except automatically substituting {@code
   * nullText} for any provided null elements.
   */
  public Joiner useForNull(String nullText) {
    checkNotNull(nullText);
    return new Joiner(this) {
      @Override
      CharSequence toString(@Nullable Object part) {