Everything you need to test, in one place

import io.restassured.RestAssured;
import static io.restassured.RestAssured.*;
import static org.hamcrest.Matchers.*;

public class UserTest {
  @Test
  public void testCreateUser() {
    RestAssured.baseURI = "https://api.example.com";

    String body = "{" +
      "\"name\": \"John\"," +
      "\"email\": \"john@test.com\"" +
    "}";

    given()
      .contentType("application/json")
      .body(body)
    .when()
      .post("/users")
    .then()
      .statusCode(201)
      .body("name", equalTo("John"))
      .body("id", notNullValue());
  }
}

import org.openqa.selenium.*;
import org.openqa.selenium.chrome.*;
import org.openqa.selenium.support.ui.*;

public class LoginTest {
  @Test
  public void testLogin() {
    WebDriver driver = new ChromeDriver();
    try {
      driver.get("https://app.example.com");
      WebDriverWait wait = new WebDriverWait(
        driver, Duration.ofSeconds(10));

      driver.findElement(By.id("email"))
        .sendKeys("test@test.com");
      driver.findElement(By.id("password"))
        .sendKeys("secret");
      driver.findElement(By.cssSelector(
        "button[type='submit']")).click();

      wait.until(ExpectedConditions
        .presenceOfElementLocated(
          By.className("dashboard")));
    } finally {
      driver.quit();
    }
  }
}