] = {} if exception_handlers is None else dict(exception_handlers)
        self.exception_handlers.setdefault(HTTPException, http_exception_handler)
        self.exception_handlers.setdefault(
            RequestValidationError, request_validation_exception_handler
        )
        self.exception_handlers.setdefault(
            WebSocketRequestValidationError,

                proxy = new Proxy(Type.HTTP, addr);
                if (StringUtil.isNotBlank(getHttpProxyUsername())) {
                    Authenticator.setDefault(new Authenticator() {
                        @Override
                        protected PasswordAuthentication getPasswordAuthentication() {

    }
  }

  @AfterEach fun tearDown() {
//    TODO reenable after https://github.com/square/okhttp/issues/8206
//    fileSystem.checkNoOpenFiles()
    cache.close()

    java.net.Authenticator.setDefault(null)
  }

  @Test
  fun get() {
    server.enqueue(MockResponse(body = "ABCDE"))
    val call = client.newCall(Request(server.url("/foo")))
    val response = call.execute()

  }

  public <T> void testNulls() {
    new NullPointerTester().testAllPublicStaticMethods(TypeToken.class);
    new NullPointerTester()
        .setDefault(TypeParameter.class, new TypeParameter<T>() {})
        .testAllPublicInstanceMethods(TypeToken.of(String.class));
  }

  private static class Assignability<From, To> {

    boolean isAssignable() {

      clientTestRule
        .newClientBuilder()
        .cache(cache)
        .cookieJar(JavaNetCookieJar(cookieManager))
        .build()
  }

  @AfterEach
  fun tearDown() {
    ResponseCache.setDefault(null)
    cache.delete()
  }

  /**
   * Test that response caching is consistent with the RI and the spec.
   * http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.4
   */
  @Test