public static <T extends @Nullable Object> Collector<T, ?, T> onlyElement() {
    return (Collector) ONLY_ELEMENT;
  }

  /**
   * This atrocity is here to let us report several of the elements in the stream if there were more
   * than one, not just two.
   */
  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  private static final class ToOptionalState {
    static final int MAX_EXTRAS = 4;

func (initialSnapShot LeakDetect) CompareCurrentSnapshot() []string {
	var stackDiff []string
	for _, g := range pickRelevantGoroutines() {
		// Identify the Go routines those were not present in the initial snapshot.
		// In other words a stack diff.
		if !initialSnapShot.relevantRoutines[g] {
			stackDiff = append(stackDiff, g)
		}
	}
	return stackDiff
}

}
```

And of course, you can define some parameters as required, some as having a default value, and some entirely optional:

{* ../../docs_src/query_params/tutorial006_py310.py hl[8] *}

In this case, there are 3 query parameters:

* `needy`, a required `str`.
* `skip`, an `int` with a default value of `0`.
* `limit`, an optional `int`.

/// tip

 * Fix: Cache SPDY responses even if the response body is closed prematurely.
 * Fix: Use strict timeouts when aborting a download.
 * Fix: Support Shoutcast HTTP responses like `ICY 200 OK`.
 * Fix: Don't unzip if there isn't a response body.
 * Fix: Don't leak gzip streams on redirects.
 * Fix: Don't do DNS lookups on invalid hosts.
 * Fix: Exhaust the underlying stream when reading gzip streams.
 * Fix: Support the `PATCH` method.

}

// MissedTasks returns the number of ILM expiry tasks that were missed since
// there were no available workers.
func (e *expiryStats) MissedTasks() int64 {
	return e.missedExpiryTasks.Load()
}

// MissedFreeVersTasks returns the number of free version collection tasks that
// were missed since there were no available workers.
func (e *expiryStats) MissedFreeVersTasks() int64 {

    return new NetworkBuilder<>(false);
  }

  /**
   * Returns a {@link NetworkBuilder} initialized with all properties queryable from {@code
   * network}.
   *
   * <p>The "queryable" properties are those that are exposed through the {@link Network} interface,
   * such as {@link Network#isDirected()}. Other properties, such as {@link
   * #expectedNodeCount(int)}, are not set in the new builder.
   */

    return new ValueGraphBuilder<>(false);
  }

  /**
   * Returns a {@link ValueGraphBuilder} initialized with all properties queryable from {@code
   * graph}.
   *
   * <p>The "queryable" properties are those that are exposed through the {@link ValueGraph}
   * interface, such as {@link ValueGraph#isDirected()}. Other properties, such as {@link
   * #expectedNodeCount(int)}, are not set in the new builder.
   */

     *
     * @return the collection of top-level phases in this lifecycle
     */
    Collection<Phase> phases();

    /**
     * Collection of main phases for this lifecycle used with the Maven 3 builders.
     * Those builders do not operate on a graph, but on the list and expect a slightly
     * different ordering (mainly unit test being executed before packaging).
     *
     * @return the collection of phases in Maven 3 compatible ordering

            // If people want to deploy it
            sb.append(LS);
            sb.append(indentation);
            sb.append("Alternatively, if you host your own repository you can deploy the file there: ");
            sb.append(LS);
            sb.append(indentation);
            sb.append("    mvn deploy:deploy-file -DgroupId=");
            sb.append(groupId);
            sb.append(" -DartifactId=");

@GwtCompatible
@ReflectionSupport(value = ReflectionSupport.Level.FULL)
// Some Android 5.0.x Samsung devices have bugs in JDK reflection APIs that cause
// getDeclaredField to throw a NoSuchFieldException when the field is definitely there.
// Since this class only needs CAS on one field, we can avoid this bug by extending AtomicReference
// instead of using an AtomicReferenceFieldUpdater. This reference stores Thread instances