* create, cache and return" pattern. For further improvements, use {@link LoadingCache} and its
   * {@link LoadingCache#get(Object) get(K)} method instead of this one.
   *
   * <p>Among the improvements that this method and {@code LoadingCache.get(K)} both provide are:
   *
   * <ul>
   *   <li>{@linkplain LoadingCache#get(Object) awaiting the result of a pending load} rather than

This can be very useful for setting up **resources** that you need to use for the whole app, and that are **shared** among requests, and/or that you need to **clean up** afterwards. For example, a database connection pool, or loading a shared machine learning model.

## Use Case { #use-case }

  }

  /**
   * Returns {@code true} if the provided keys are among the keys provided when the table was
   * constructed.
   */
  @Override
  public boolean contains(@Nullable Object rowKey, @Nullable Object columnKey) {
    return containsRow(rowKey) && containsColumn(columnKey);
  }

  /**
   * Returns {@code true} if the provided column key is among the column keys provided when the
   * table was constructed.
   */

## Benchmarks and speed { #benchmarks-and-speed }

When you check the benchmarks, it is common to see several tools of different types compared as equivalent.

Specifically, to see Uvicorn, Starlette and FastAPI compared together (among many other tools).

The simpler the problem solved by the tool, the better performance it will get. And most of the benchmarks don't test the additional features provided by the tool.

The hierarchy is like:

There are several alternatives, including:

* [Uvicorn](https://www.uvicorn.dev/): a high performance ASGI server.
* [Hypercorn](https://hypercorn.readthedocs.io/): an ASGI server compatible with HTTP/2 and Trio among other features.
* [Daphne](https://github.com/django/daphne): the ASGI server built for Django Channels.
* [Granian](https://github.com/emmett-framework/granian): A Rust HTTP server for Python applications.

   * values in the list are not supported.
   *
   * <p>The returned comparator throws a {@link ClassCastException} when it receives an input
   * parameter that isn't among the provided values.
   *
   * <p>The generated comparator is serializable if all the provided values are serializable.
   *
   * @param valuesInOrder the values that the returned comparator will be able to compare, in the

   * values in the list are not supported.
   *
   * <p>The returned comparator throws a {@link ClassCastException} when it receives an input
   * parameter that isn't among the provided values.
   *
   * <p>The generated comparator is serializable if all the provided values are serializable.
   *
   * @param valuesInOrder the values that the returned comparator will be able to compare, in the

      return topDown(startNodes, InsertionOrder.FRONT);
    }

    /**
     * In top-down traversal, an ancestor node is always traversed before any of its descendant
     * nodes. The traversal order among descendant nodes (particularly aunts and nieces) are
     * determined by the {@code InsertionOrder} parameter: nieces are placed at the FRONT before
     * aunts for pre-order; while in BFS they are placed at the BACK after aunts.

When you run **multiple processes** of the same API program, they are commonly called **workers**.

### Worker Processes and Ports { #worker-processes-and-ports }

        assertTrue(extraFieldNames.contains("aaa_field"));
        assertTrue(extraFieldNames.contains("mmm_field"));
        assertTrue(extraFieldNames.contains("zzz_field"));
        // Verify sorted order among the custom fields
        final int aIdx = extraFieldNames.indexOf("aaa_field");
        final int mIdx = extraFieldNames.indexOf("mmm_field");
        final int zIdx = extraFieldNames.indexOf("zzz_field");