request.addHeader("Host", "example.com");
        key = virtualHostHelper.getVirtualHostKey();
        assertEquals("", key); // Still empty due to caching

        // Test caching by calling again - should return cached value
        key = virtualHostHelper.getVirtualHostKey();
        assertEquals("", key); // Still cached value
    }

    @Test
    public void test_getVirtualHostKey_withCaching() {

   * Returns the index of the first matching BMP character in a character sequence, or {@code -1} if
   * no matching character is present.
   *
   * <p>The default implementation iterates over the sequence in forward order calling {@link
   * #matches} for each character.
   *
   * @param sequence the character sequence to examine from the beginning
   * @return an index, or {@code -1} if no character matches
   */

   * <p>The returned fluent iterable's iterator supports {@code remove()} if the {@code Iterator} of
   * this fluent iterable supports it. Note that it is <i>not</i> possible to delete the last
   * skipped element by immediately calling {@code remove()} on the returned fluent iterable's
   * iterator, as the {@code Iterator} contract states that a call to {@code * remove()} before a
   * call to {@code next()} will throw an {@link IllegalStateException}.
   *

// TFE_ExecutorWaitForAllPendingNodes before calling this API if you want to
// make sure all nodes are finished.
TF_CAPI_EXPORT extern void TFE_DeleteExecutor(TFE_Executor*);

// Returns true if the executor is in async mode.
TF_CAPI_EXPORT extern bool TFE_ExecutorIsAsync(TFE_Executor*);

// Causes the calling thread to block till all ops dispatched in this executor

 * instances:
 *
 * <ul>
 *   <li>If you receive them from an {@code java.util.concurrent.ExecutorService}, convert that
 *       service to a {@link ListeningExecutorService}, usually by calling {@link
 *       MoreExecutors#listeningDecorator(java.util.concurrent.ExecutorService)
 *       MoreExecutors.listeningDecorator}.
 *   <li>If you manually call {@link java.util.concurrent.FutureTask#set} or a similar method,

 *   <li>a {@linkplain ThreadFactory#newThread backing thread factory}
 * </ul>
 *
 * <p>If no backing thread factory is provided, a default backing thread factory is used as if by
 * calling {@code setThreadFactory(}{@link Executors#defaultThreadFactory()}{@code )}.
 *
 * <p><b>Java 21+ users:</b> consider using the {@code Thread.Builder} interface instead. E.g.,

   *
   * @since 11.0
   */
  void put(K key, V value);

  /**
   * Copies all of the mappings from the specified map to the cache. The effect of this call is
   * equivalent to that of calling {@code put(k, v)} on this map once for each mapping from key
   * {@code k} to value {@code v} in the specified map. The behavior of this operation is undefined
   * if the specified map is modified while the operation is in progress.

				Computed: etag,
			}
		}
	}
	return n, err
}

// ETag returns the ETag of all the content read
// so far. Reading more content changes the MD5
// checksum. Therefore, calling ETag multiple
// times may return different results.
func (r *Reader) ETag() ETag {
	sum := r.md5.Sum(nil)
	return ETag(sum)
}

// VerifyError is an error signaling that a

 * instances:
 *
 * <ul>
 *   <li>If you receive them from an {@code java.util.concurrent.ExecutorService}, convert that
 *       service to a {@link ListeningExecutorService}, usually by calling {@link
 *       MoreExecutors#listeningDecorator(java.util.concurrent.ExecutorService)
 *       MoreExecutors.listeningDecorator}.
 *   <li>If you manually call {@link java.util.concurrent.FutureTask#set} or a similar method,

		// them if they could be an ancestor of an
		// aggregation.
	}
	return nil
}

// getAggregate() implementation for each AST node follows. This is
// called after calling aggregateRow() on each input row, to calculate
// the final aggregate result.

func (e *FuncExpr) getAggregate() (*Value, error) {
	switch e.getFunctionName() {
	case aggFnCount: