Blocking APIs may be inefficient because you hold a thread idle while waiting on the network. Threads are expensive because they have both a memory overhead and a context-switching overhead.

#### Framed protocols

 * `::1` will reach the IPv6 server.
 *
 * By orchestrating two different servers with the same port but different IP addresses, we can
 * test what OkHttp does when both are reachable, or if only one is reachable.
 *
 * This test only runs on host machines that have both IPv4 and IPv6 addresses for localhost.
 */
@Timeout(30)
class FastFallbackTest {
  @RegisterExtension
  val clientTestRule = OkHttpClientTestRule()

  }

  @Override
  public void clear() {
    if (needsAllocArrays()) {
      return;
    }
    this.firstEntry = ENDPOINT;
    this.lastEntry = ENDPOINT;
    // Either both arrays are null or neither is, but we check both to satisfy the nullness checker.
    if (predecessor != null && successor != null) {
      Arrays.fill(predecessor, 0, size(), 0);
      Arrays.fill(successor, 0, size(), 0);
    }

  }

  @Override
  public void clear() {
    if (needsAllocArrays()) {
      return;
    }
    this.firstEntry = ENDPOINT;
    this.lastEntry = ENDPOINT;
    // Either both arrays are null or neither is, but we check both to satisfy the nullness checker.
    if (predecessor != null && successor != null) {
      Arrays.fill(predecessor, 0, size(), 0);
      Arrays.fill(successor, 0, size(), 0);
    }

  /**
   * Returns the set of values that are contained in both this set and the other.
   *
   * <p>This method should always be used instead of {@link Sets#intersection} for {@link
   * ContiguousSet} instances.
   */
  public abstract ContiguousSet<C> intersection(ContiguousSet<C> other);

  /**
   * Returns a range, closed on both ends, whose endpoints are the minimum and maximum values

* **Harder for non-native speakers**: Contributors and users for whom English is a second language benefit from a single, consistent convention

While both American and British English are valid, establishing a single standard improves consistency, readability, and maintainability of the codebase.

## Decision

func TestXFFDisabled(t *testing.T) {
	req := &http.Request{
		Header: http.Header{
			xForwardedFor: []string{"8.8.8.8"},
			xRealIP:       []string{"1.1.1.1"},
		},
	}
	// When X-Forwarded-For and X-Real-IP headers are both present, X-Forwarded-For takes precedence.
	res := GetSourceIP(req)
	if res != "8.8.8.8" {
		t.Errorf("wrong header, xff takes precedence: got %s, want: 8.8.8.8", res)
	}

  /**
   * The reason why this stream was closed, or null if it closed normally or has not yet been
   * closed.
   *
   * If there are multiple reasons to abnormally close this stream (such as both peers closing it
   * near-simultaneously) then this is the first reason known to this peer.
   */
  internal var errorCode: ErrorCode? = null
    get() = withLock { field }

                  public Integer load(Integer from) {
                    return (int) misses.incrementAndGet();
                  }
                });

    // To start, fill up the cache.
    // Each miss both increments the counter and causes the map to grow by one,
    // so until evictions begin, the size of the map is the greatest return
    // value seen so far
    while (cache.getUnchecked(nextRandomKey()) < maximumSize) {}

@GwtCompatible
public final class HtmlEscapers {
  /**
   * Returns an {@link Escaper} instance that escapes HTML metacharacters as specified by <a
   * href="http://www.w3.org/TR/html4/">HTML 4.01</a>. The resulting strings can be used both in
   * attribute values and in most elements' text contents, provided that the HTML
   * document's character encoding can encode any non-ASCII code points in the input (as UTF-8 and
   * other Unicode encodings can).