Spring:MockWebServer

class MathServiceTest {
    private MathService service;
    private MockWebServer server;
    
    @BeforeEach
    void setUp() throws IOException {
        server = new MockWebServer();
        server.start();
        String rootUrl = server.url("/api/").toString();
        service = new MathService(WebClient.create(rootUrl));
    }
    
    // TODO: write tests
}