# Calls

The HTTP client’s job is to accept your request and produce its response. This is simple in theory but it gets tricky in practice.

## [Requests](https://square.github.io/okhttp/5.x/okhttp/okhttp3/-request/)

Each HTTP request contains a URL, a method (like `GET` or `POST`), and a list of headers. Requests may also contain a body: a data stream of a specific content type.

## [Responses](https://square.github.io/okhttp/5.x/okhttp/okhttp3/-response/)

/**
 * Tests for {@link PercentEscaper}.
 *
 * @author David Beaumont
 */
@GwtCompatible
@NullUnmarked
public class PercentEscaperTest extends TestCase {

  /** Tests that the simple escaper treats 0-9, a-z and A-Z as safe */
  public void testSimpleEscaper() {
    UnicodeEscaper e = new PercentEscaper("", false);
    for (char c = 0; c < 128; c++) {

 * TODO: javadoc.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public abstract class TestStringListGenerator implements TestListGenerator<String> {
  @Override
  public SampleElements<String> samples() {
    return new Strings();
  }

  @Override
  public List<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {

 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public abstract class TestStringMultisetGenerator implements TestMultisetGenerator<String> {
  @Override
  public SampleElements<String> samples() {
    return new Strings();
  }

  @Override
  public Multiset<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {

## Declaring types { #declaring-types }

You just saw the main place to declare type hints. As function parameters.

This is also the main place you would use them with **FastAPI**.

### Simple types { #simple-types }

You can declare all the standard Python types, not only `str`.

You can use, for example:

* `int`
* `float`
* `bool`
* `bytes`

 *
 * @author Gregory Kick
 */
@GwtCompatible
@NullMarked
public abstract class TestIntegerSetGenerator implements TestSetGenerator<Integer> {
  @Override
  public SampleElements<Integer> samples() {
    return new Ints();
  }

  @Override
  public Set<Integer> create(Object... elements) {
    Integer[] array = new Integer[elements.length];
    int i = 0;
    for (Object e : elements) {

 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public abstract class TestEnumMultisetGenerator implements TestMultisetGenerator<AnEnum> {
  @Override
  public SampleElements<AnEnum> samples() {
    return new Enums();
  }

  @Override
  public Multiset<AnEnum> create(Object... elements) {
    AnEnum[] array = new AnEnum[elements.length];
    int i = 0;
    for (Object e : elements) {

 * [OkHttp Idling Resource](https://github.com/JakeWharton/okhttp-idling-resource): An Espresso IdlingResource for OkHttp.
 * [okhttp-client-mock](https://github.com/gmazzo/okhttp-client-mock): A simple OKHttp client mock, using a programmable request interceptor.
 * [OkHttp Profiler](https://plugins.jetbrains.com/plugin/11249-okhttp-profiler): An IntelliJ plugin for monitoring OkHttp calls.

 * @author George van den Driessche
 */
@GwtCompatible
@NullMarked
public abstract class TestStringMapGenerator implements TestMapGenerator<String, String> {

  @Override
  public SampleElements<Entry<String, String>> samples() {
    return new SampleElements<>(
        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));

 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public abstract class TestStringCollectionGenerator implements TestCollectionGenerator<String> {
  @Override
  public SampleElements<String> samples() {
    return new Strings();
  }

  @Override
  public Collection<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {