protected final ListenableFutureTask<Integer> task =
      ListenableFutureTask.create(
          new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {
              runLatch.countDown();
              taskLatch.await();
              if (throwException) {
                throw new IllegalStateException("Fail");
              }

        // Assert
        assertNull(ex.getCause(), "Null cause should be preserved");
        assertNotNull(ex.toString(), "toString should be safe to call");
    }

    @ParameterizedTest
    @NullAndEmptySource
    @ValueSource(strings = { "oops", "multi word", "中文" })
    @DisplayName("Message+Cause constructor: preserves both values; no interactions with cause")

        assertFalse(map.containsValue(valueOne));
        assertNull(map.get(keyOne));
        assertEquals(1, map.size());
        assertNull(segment.getKeyReferenceQueueForTesting().poll());
      }
    }
  }

  public void testDrainValueReferenceQueueOnWrite() {
    for (MapMaker maker : allWeakValueStrengthMakers()) {

        assertFalse(map.containsValue(valueOne));
        assertNull(map.get(keyOne));
        assertEquals(1, map.size());
        assertNull(segment.getKeyReferenceQueueForTesting().poll());
      }
    }
  }

  public void testDrainValueReferenceQueueOnWrite() {
    for (MapMaker maker : allWeakValueStrengthMakers()) {

  }

  /**
   * Specifies the maximum weight of entries the cache may contain. Weight is determined using the
   * {@link Weigher} specified with {@link #weigher}, and use of this method requires a
   * corresponding call to {@link #weigher} prior to calling {@link #build}.
   *
   * <p>Note that the cache <b>may evict an entry before this limit is exceeded</b>. For example, in

	Spectre    = flag.String("spectre", "", "enable spectre mitigations in `list` (all, ret)")
)

var DebugFlags struct {
	MayMoreStack string `help:"call named function before all stack growth checks"`
	PCTab        string `help:"print named pc-value table\nOne of: pctospadj, pctofile, pctoline, pctoinline, pctopcdata"`
}

var (
	D        MultiFlag
	I        MultiFlag

            int expectedSize = request.size();

            // Call size multiple times
            for (int i = 0; i < 1000; i++) {
                assertEquals(expectedSize, request.size());
            }

            assertEquals(1001, request.getSizeCallCount()); // Including initial call
        }
    }

$ python main.py

// As we didn't set the env var, we get the default value

Hello World from Python

// But if we create an environment variable first
$ export MY_NAME="Wade Wilson"

// And then call the program again
$ python main.py

// Now it can read the environment variable

Hello Wade Wilson from Python
```

</div>

////

//// tab | Windows PowerShell

<div class="termy">

// 500 Internal Server Error.
type MetricsLoaderFn func(context.Context, MetricValues, *metricsCache) error

// JoinLoaders - joins multiple loaders into a single loader. The returned
// loader will call each of the given loaders in order. If any of the loaders
// return an error, the returned loader will return that error.
func JoinLoaders(loaders ...MetricsLoaderFn) MetricsLoaderFn {

```

## EventListener events 

Cache Events are exposed via the EventListener API.  Typical scenarios are below.

### Cache Hit

In the ideal scenario the cache can fulfill the request without any conditional call to the network.
This will skip the normal events such as DNS, connecting to the network, and downloading the response body.

As recommended by the HTTP RFC the max age of a document is defaulted to 10% of the