* the discussion in the {@link #addListener} documentation. All its warnings about heavyweight
   * listeners are also applicable to heavyweight functions passed to this method.
   *
   * <p>This method is similar to {@link java.util.concurrent.CompletableFuture#exceptionally}. It
   * can also serve some of the use cases of {@link java.util.concurrent.CompletableFuture#handle}

You can verify it in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/request-form-models/image01.png">
</div>

## Forbid Extra Form Fields { #forbid-extra-form-fields }

In some special use cases (probably not very common), you might want to **restrict** the form fields to only those declared in the Pydantic model. And **forbid** any **extra** fields.

/// note

			// directory" error message. Handle this specifically
			// here.
			return errFileAccessDenied
		}
	}
	return err
}

// Reliably retries os.RemoveAll if for some reason os.RemoveAll returns
// syscall.ENOTEMPTY (children has files).
func reliableRemoveAll(dirPath string) (err error) {
	i := 0
	for {
		// Removes all the directories and files.

            }
            // Simulate some encoding activity on the buffer
            dst.enc_ndr_long(123);
        }

        @Override
        public void decode(NdrBuffer src) throws NdrException {
            if (throwOnDecode) {
                throw new NdrException("Failed to decode");
            }
            // Simulate some decoding activity on the buffer
            src.dec_ndr_long();

## Apelidos (alias) de parâmetros

Imagine que você queira que um parâmetro tenha o nome `item-query`.

Desta maneira:

```
http://127.0.0.1:8000/items/?item-query=foobaritems
```

Mas o nome `item-query` não é um nome de váriavel válido no Python.

O que mais se aproxima é `item_query`.

Mas ainda você precisa que o nome seja exatamente `item-query`...

    @Test
    public void testReset() throws Exception {
        // Create some state
        String username = "resettest";
        String ip = "192.168.1.12";

        for (int i = 0; i < 2; i++) {
            rateLimiter.checkAttempt(username, ip);
            rateLimiter.recordFailure(username, ip);
        }

        // Should have some state

    for (StandardSystemProperty property : StandardSystemProperty.values()) {
      // Even though the contract in System.getProperties() specifies that a value will exist for
      // all of the listed keys, for some reason the "java.compiler" key returns null in some JVMs.
      if (property == JAVA_COMPILER) {
        continue;
      }
      // Removed in Java 9:

            pomArtifact = rel.pomArtifact;

            relocatedArtifact = rel.relocatedArtifact;

            if (rel.project == null) {
                // When this happens we have a Maven 1.x POM, or some invalid POM.
                // It should have never found its way into Maven 2.x repository, but it did.
                dependencies = Collections.emptyList();
            } else {

	// Create a buffer to write our archive to.
	buf := new(bytes.Buffer)

	// Create a new zip archive.
	w := zip.NewWriter(buf)

	// Add some files to the archive.
	var files = []struct {
		Name, Body string
	}{
		{"readme.txt", "This archive contains some text files."},
		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
		{"todo.txt", "Get animal handling licence.\nWrite more examples."},
	}

   * expect, but there are some subtleties. First, we do guarantee that, if the output future at
   * index n is done, the output future at index n-1 is also done. (But as usual with futures, some
   * listeners for future n may complete before some for future n-1.) However, it is possible, if
   * one input completes with result X and another later with result Y, for Y to come before X in