This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

 * }</pre>
 *
 * <p><b>Warning:</b> Be extremely careful what you do with conceptually large instances (such as
 * {@code ContiguousSet.create(Range.greaterThan(0), DiscreteDomain.integers()}). Certain operations
 * on such a set can be performed efficiently, but others (such as {@link Set#hashCode} or {@link
 * Collections#frequency}) can cause major performance problems.
 *
 * @author Gregory Kick
 * @since 10.0
 */

import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.Map.Entry;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code clear()} operations on a map. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author George van den Driessche
 * @author Chris Povirk
 */
@GwtCompatible

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code toString()} operations on a map. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@GwtCompatible

import com.google.common.collect.testing.features.CollectionSize;
import java.lang.reflect.Method;
import java.util.List;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code add(Object)} operations on a list. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible(emulated = true)

import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code get} operations on a map. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@GwtCompatible

Mas, você já sabe como criar facilmente documentação automática para uma API com o **FastAPI**.

Então vamos usar esse mesmo conhecimento para documentar como a *API externa* deveria ser... criando as *operações de rota* que a *API externa* deveria implementar (as que sua API irá chamar).

/// tip | Dica

Esses são objetos **JavaScript**, não strings, então você não pode passá-los diretamente do código Python.

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Map.Entry;
import java.util.concurrent.ConcurrentMap;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code putIfAbsent} operations on a concurrent map. Can't be
 * invoked directly; please see {@link
 * com.google.common.collect.testing.ConcurrentMapTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

# GraphQL

As **FastAPI** is based on the **ASGI** standard, it's very easy to integrate any **GraphQL** library also compatible with ASGI.

You can combine normal FastAPI *path operations* with GraphQL on the same application.

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.