## Retrying Requests

Sometimes connections fail: either a pooled connection was stale and disconnected, or the webserver itself couldn’t be reached. OkHttp will retry the request with a different route if one is available.

      MockResponse(
        code = 503,
        headers = headersOf("Retry-After", "0"),
        body = "please retry",
      ),
    )
    server.enqueue(
      MockResponse(body = "thank you for retrying"),
    )
    val request =
      Request(
        url = server.url("/"),
        body =
          object : RequestBody() {
            var attempt = 0

     * * **Unreachable proxy servers.** A [ProxySelector] can be used to
     *   attempt multiple proxy servers in sequence, eventually falling back to a direct
     *   connection.
     *
     * Set this to false to avoid retrying requests when doing so is destructive. In this case the
     * calling application should do its own recovery of connectivity failures.
     */
    fun retryOnConnectionFailure(retryOnConnectionFailure: Boolean) =

- The kubelet plugin manager now properly handles plugin registration failures by removing failed plugins from the actual state and retrying with exponential backoff (initial delay 500ms, doubling each failure up to ~2 minutes maximum) to protect against broken plugins causing denial of service while still allowing recovery from transient failures. ([#133335](https://github.com/kuber...

            return result;
          }
        }

        // didn't see it, trying to put it instead...
        Dummy sneaky = map.putIfAbsent(sample, Dummy.VALUE);
        if (sneaky == null) {
          return sample;
        } else {
          /* Someone beat us to it! Trying again...
           *
           * Technically this loop not guaranteed to terminate, so theoretically (extremely

            return result;
          }
        }

        // didn't see it, trying to put it instead...
        Dummy sneaky = map.putIfAbsent(sample, Dummy.VALUE);
        if (sneaky == null) {
          return sample;
        } else {
          /* Someone beat us to it! Trying again...
           *
           * Technically this loop not guaranteed to terminate, so theoretically (extremely

 * variety of sequences of the {@link Iterator#next}, {@link Iterator#hasNext} and {@link
 * Iterator#remove} operations. This utility takes the brute-force approach of trying <i>all</i>
 * possible sequences of these operations, up to a given number of steps. So, if the caller
 * specifies to use <i>n</i> steps, a total of <i>3^n</i> tests are actually performed.
 *

    GoodEquals(@SuppressWarnings("unused") NotInstantiable x) {
      this.a = "x";
      this.b = -1;
    }

    // will keep trying
    public GoodEquals(@SuppressWarnings("unused") NotInstantiable x, int b) {
      this.a = "x";
      this.b = b;
    }

    // keep trying
    @Keep
    static GoodEquals create(int a, int b) {
      throw new RuntimeException();
    }

    // Good!

/// info

FastAPI added support for `Annotated` (and started recommending it) in version 0.95.0.

If you have an older version, you would get errors when trying to use `Annotated`.

Make sure you [Upgrade the FastAPI version](../deployment/versions.md#upgrading-the-fastapi-versions) to at least 0.95.1 before using `Annotated`.

///

## Declare metadata { #declare-metadata }

  public void testAssignableParameterizedTypeToClass() {
    @SuppressWarnings("rawtypes") // Trying to test raw class
    TypeToken<List> tokL = new TypeToken<List>() {};
    assertTrue(tokL.isSupertypeOf(StringList.class));
    assertTrue(tokL.isSupertypeOf(StringList.class.getGenericInterfaces()[0]));

    @SuppressWarnings("rawtypes") // Trying to test raw class
    TypeToken<Second> tokS = new TypeToken<Second>() {};