And of course, it supports the same:

* data validation
* data serialization
* data documentation, etc.

This works the same way as with Pydantic models. And it is actually achieved in the same way underneath, using Pydantic.

/// info

Keep in mind that dataclasses can't do everything Pydantic models can do.

/**
 * Unit test for {@link Ascii}.
 *
 * @author Craig Berry
 */
@GwtCompatible
public class AsciiTest extends TestCase {

  /**
   * The Unicode points {@code 00c1} and {@code 00e1} are the upper- and lowercase forms of
   * A-with-acute-accent, {@code Á} and {@code á}.
   */
  private static final String IGNORED = "`10-=~!@#$%^&*()_+[]\\{}|;':\",./<>?'\u00c1\u00e1\n";

  private static final String LOWER = "abcdefghijklmnopqrstuvwxyz";

	SHLL	CX, R12
	SHLL	CX, foo+4(SB)
	// Old syntax, still accepted:
	SHLL	CX, R11:AX // SHLL CX, AX, R11

// LTYPEM spec6	{ outcode($1, &$2); }
	MOVL	AX, R11
	MOVL	$4, R11
//	MOVL	AX, 0(AX):DS // no longer works - did it ever?

// LTYPEI spec7	{ outcode($1, &$2); }
	IMULB	DX
	IMULW	DX, BX
	IMULL	R11, R12
	IMULQ	foo+4(SB), R11

// LTYPEXC spec8	{ outcode($1, &$2); }
	CMPPD	X1, X2, 4
	CMPPD	foo+4(SB), X2, 4

import java.util.List;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.repository.RepositoryRequest;

/**
 * Forms a request to retrieve artifact metadata.
 *
 */
@Deprecated
public interface MetadataResolutionRequest extends RepositoryRequest {

    /**

    `com.google.guava:failureaccess:1.0.2`. It also has
    [some annotation-only dependencies][guava-deps], which we discuss in more
    detail at that link.

4.  Serialized forms of ALL objects are subject to change unless noted
    otherwise. Do not persist these and assume they can be read by a future
    version of the library.

The whole **FastAPI** framework is based to satisfy that. Autocompletion works everywhere.

You will rarely need to come back to the docs.

Here's how your editor might help you:

* in <a href="https://code.visualstudio.com/" class="external-link" target="_blank">Visual Studio Code</a>:

In fact, in some cases, it will even have **two JSON Schemas** in OpenAPI for the same Pydantic model, for input and output, depending on if they have **default values**.

Let's see how that works and how to change it if you need to do that.

## Pydantic Models for Input and Output

Let's say you have a Pydantic model with default values, like this one:

      fail("setValue on unmodifiable Map.Entry succeeded");
    } catch (UnsupportedOperationException expected) {
    }
  }

  /**
   * Verifies that an Iterator is unmodifiable.
   *
   * <p>This test only works with iterators that iterate over a finite set.
   */
  public static void assertIteratorIsUnmodifiable(Iterator<?> iterator) {
    while (iterator.hasNext()) {
      iterator.next();
      try {
        iterator.remove();

All these, while minimizing code repetition.

## First Steps

Let's see a very simple example. It will be so simple that it is not very useful, for now.

But this way we can focus on how the **Dependency Injection** system works.

### Create a dependency, or "dependable"

Let's first focus on the dependency.

It is just a function that can take all the same parameters that a *path operation function* can take:

      byte[] got = out.toByteArray();
      for (int i = 0; i < expected.length; i++) {
        assertEquals(expected[i], got[i]);
      }
    }
  }

  // Assumes that AbstractNonStreamingHashFunction works properly (must be tested elsewhere!)
  private static class Control extends AbstractNonStreamingHashFunction {
    @Override
    public HashCode hashBytes(byte[] input, int off, int len) {