/**
 * A {@link ListenableFuture} which forwards all its method calls to another future. Subclasses
 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
 *
 * @author Shardul Deo
 * @since 4.0
 */

/**
 * A {@link ListenableFuture} which forwards all its method calls to another future. Subclasses
 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
 *
 * @author Shardul Deo
 * @since 4.0
 */

import java.util.Iterator;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A map which forwards all its method calls to another map. Subclasses should override one or more
 * methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

import java.util.concurrent.Callable;
import org.jspecify.annotations.Nullable;

/**
 * A listening executor service which forwards all its method calls to another listening executor
 * service. Subclasses should override one or more methods to modify the behavior of the backing
 * executor service as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.List;
import org.jspecify.annotations.Nullable;

/**
 * A list multimap which forwards all its method calls to another list multimap. Subclasses should
 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

public abstract class ForwardingObject {

  /** Constructor for use by subclasses. */
  protected ForwardingObject() {}

  /**
   * Returns the backing delegate instance that methods are forwarded to. Abstract subclasses
   * generally override this method with an abstract method that has a more specific return type,
   * such as {@link ForwardingSet#delegate}. Concrete subclasses override this method to supply the
   * instance being decorated.
   */

 *
 * <p>In addition to {@link #execute}, subclasses must implement all methods related to shutdown and
 * termination.
 *
 * @author Chris Povirk
 * @since 14.0
 */
@CheckReturnValue
@GwtIncompatible
public abstract class AbstractListeningExecutorService extends AbstractExecutorService
    implements ListeningExecutorService {
  /** Constructor for use by subclasses. */
  public AbstractListeningExecutorService() {}

   * </ul>
   *
   * <p>Subclasses can override this method to provide custom equality.
   */
  @Override
  public boolean equals(@Nullable Object obj) {
    return super.equals(obj);
  }

  /**
   * By default delegates to {@link Object#hashCode}. The dynamic proxies' {@code hashCode()} will
   * delegate to this method. Subclasses can override this method to provide custom equality.
   */

import java.util.Comparator;
import java.util.NoSuchElementException;
import java.util.SortedMap;
import org.jspecify.annotations.Nullable;

/**
 * A sorted map which forwards all its method calls to another sorted map. Subclasses should
 * override one or more methods to modify the behavior of the backing sorted map as desired per the
 * <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

Na realidade, `Query`, `Path` e outros que você verá em seguida, criam objetos de subclasses de uma classe `Param` comum, que é ela mesma uma subclasse da classe `FieldInfo` do Pydantic.

E `Field` do Pydantic retorna uma instância de `FieldInfo` também.

`Body` também retorna objetos de uma subclasse de `FieldInfo` diretamente. E tem outras que você verá mais tarde que são subclasses da classe `Body`.