statsCounter.recordLoadException(ticker.read() - startTime);
      throw new ExecutionError(e);
    }

    if (calculatedValue == null) {
      String message = loader + " returned null for key " + key + ".";
      throw new CacheLoader.InvalidCacheLoadException(message);
    }
    statsCounter.recordLoadSuccess(ticker.read() - startTime);
    return calculatedValue;
  }

  private V getIfPresent(Object key) {

{* ../../docs_src/custom_response/tutorial009c.py hl[9:14,17] *}

Agora em vez de retornar:

```json
{"message": "Hello World"}
```

...essa resposta retornará:

```json
{
  "message": "Hello World"
}
```

Obviamente, você provavelmente vai encontrar maneiras muito melhores de se aproveitar disso do que a formatação de JSON. 😉

<h3 id="Type_unification_rules">Type unification rules</h3>

<p>
The type unification rules describe if and how two types unify.
The precise details are relevant for Go implementations,
affect the specifics of error messages (such as whether
a compiler reports a type inference or other error),
and may explain why type inference fails in unusual code situations.
But by and large these rules can be ignored when writing Go code:

          connectionCount.incrementAndGet()
          service(socket)
        }
      } catch (e: SocketException) {
        logger.info("$threadName done accepting connections: ${e.message}")
      } catch (e: IOException) {
        logger.log(Level.WARNING, "$threadName failed unexpectedly", e)
      } finally {
        for (socket in openSockets) {
          socket.closeQuietly()
        }

      key = "has_space "
      cache.edit(key)
    }.also { expected ->
      assertThat(expected.message).isEqualTo("keys must match regex [a-z0-9_-]{1,120}: \"$key\"")
    }
    assertFailsWith<IllegalArgumentException> {
      key = "has_CR\r"
      cache.edit(key)
    }.also { expected ->
      assertThat(expected.message).isEqualTo("keys must match regex [a-z0-9_-]{1,120}: \"$key\"")
    }

        });
    }

    /**
     * Generates a hashed ID from the provided URL ID string.
     * Encodes special characters using URL encoding or Base64 encoding as needed,
     * then applies a message digest algorithm to create a unique hash.
     *
     * @param urlId the URL ID string to generate a hash for
     * @return a hashed ID string generated from the input URL ID
     */

  @Synchronized
  fun runningCallsCount(): Int = runningAsyncCalls.size + runningSyncCalls.size

  @JvmName("-deprecated_executorService")
  @Deprecated(
    message = "moved to val",
    replaceWith = ReplaceWith(expression = "executorService"),
    level = DeprecationLevel.ERROR,
  )
  fun executorService(): ExecutorService = executorService

        .addEqualityGroup(wrapperFunction.apply(generator.newFreshProxy(interfaceType)))
        // TODO: add an overload to EqualsTester to print custom error message?
        .testEquals();
  }

  private static <T> void testToString(
      Class<T> interfaceType, Function<? super T, ? extends T> wrapperFunction) {

{* ../../docs_src/background_tasks/tutorial001.py hl[14] *}

`.add_task()` 함수는 다음과 같은 인자를 받습니다 :

- 백그라운드에서 실행되는 작업 함수 (`write_notification`).
- 작업 함수에 순서대로 전달되어야 하는 일련의 인자 (`email`).
- 작업 함수에 전달되어야하는 모든 키워드 인자 (`message="some notification"`).

## 의존성 주입

`BackgroundTasks`를 의존성 주입 시스템과 함께 사용하면 _경로 작동 함수_, 종속성, 하위 종속성 등 여러 수준에서 BackgroundTasks 유형의 매개변수를 선언할 수 있습니다.

        CGO_CXXFLAGS="-O2 -g"
        CGO_FFLAGS="-O2 -g"
        CGO_LDFLAGS="-O2 -g"
        PKG_CONFIG="pkg-config"
        GOGCCFLAGS="-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/44/nbbyll_10jd0z8rj_qxm43740000gn/T/go-build2331607515=/tmp/go-build -gno-record-gcc-switches -fno-common"
      render: shell
    validations:
      required: true