public int hashCode() {
    return delegate.hashCode();
  }

  private void validate() {
    // Don't use checkState(), because we don't want the overhead of generating the error message
    // unless it's actually going to be used; validate() is called for all set method calls, so it
    // needs to be fast.
    // (We could instead generate the message once, when the set is created, but zero is better.)
    if (!validator.get()) {

          // reset state in case of an error so that later dispatch calls will actually do something
          synchronized (this) {
            isThreadScheduled = false;
          }
          // Log it and keep going.
          logger
              .get()
              .log(
                  Level.SEVERE,
                  "Exception while running callbacks for " + listener + " on " + executor,
                  e);

```

But possibly the most important part of the callback is making sure that your API user (the external developer) implements the *external API* correctly, according to the data that *your API* is going to send in the request body of the callback, etc.

So, what we will do next is add the code to document how that *external API* should look like to receive the callback from *your API*.

  public int hashCode() {
    return delegate.hashCode();
  }

  private void validate() {
    // Don't use checkState(), because we don't want the overhead of generating the error message
    // unless it's actually going to be used; validate() is called for all set method calls, so it
    // needs to be fast.
    // (We could instead generate the message once, when the set is created, but zero is better.)
    if (!validator.get()) {

* [MinIO Erasure Code QuickStart Guide](https://docs.min.io/community/minio-object-store/operations/concepts/erasure-coding.html)...

   */
  @Override
  public float floatValue() {
    if (value >= 0) {
      return (float) value;
    }
    // The top bit is set, which means that the float value is going to come from the top 24 bits.
    // So we can ignore the bottom 8, except for rounding. See doubleValue() for more.
    return (float) ((value >>> 1) | (value & 1)) * 2f;
  }

  /**

## OpenAPI and API docs { #openapi-and-api-docs }

If you return additional status codes and responses directly, they won't be included in the OpenAPI schema (the API docs), because FastAPI doesn't have a way to know beforehand what you are going to return.

     */
    return (int) Math.pow(a, 1.0 / concentration);
  }

  @AfterExperiment
  void tearDown() {
    double req = requests.get();
    double hit = req - misses.get();

    // Currently, this is going into /dev/null, but I'll fix that
    System.out.println("hit rate: " + hit / req);
  }

  // for proper distributions later:
  // import JSci.maths.statistics.ProbabilityDistribution;

        result = KuromojiCSVUtil.parse(value);
        assertEquals(4, result.length);
        assertEquals("John Doe", result[0]);
        assertEquals("Software Engineer", result[1]);
        assertEquals("******@****.***", result[2]);
        assertEquals("\"Loves \"\"coding\"\" and coffee\"", result[3]);

    arraycopy(contents, 0, result, 0, contents.length);
    return result;
  }

  /*
   * a "type A" unmodifiable collection freaks out proactively, even if there
   * wasn't going to be any actual work to do anyway
   */

  @Override
  public boolean addAll(Collection<? extends E> elementsToAdd) {
    throw up();
  }

  @Override