removeWaiter(node);
                break long_wait_loop; // jump down to the busy wait loop
              }
            }
          }
          oldHead = waitersField; // re-read and loop.
        } while (oldHead != Waiter.TOMBSTONE);
      }
      // re-read valueField, if we get here then we must have observed a TOMBSTONE while trying to

      assertThat(response.body.string()).contains("h=cloudflare-dns.com")
    }
  }

  @Test
  fun getWithDns() {
    client =
      client
        .newBuilder()
        .dns {
          Dns.SYSTEM.lookup("sni.cloudflaressl.com")
        }.build()

    val request =
      Request
        .Builder()
        .url("https://cloudflare-dns.com/cdn-cgi/trace")
        .build()

    .build()
```

Kotlin calling OkHttp 4.x:

```kotlin
val client = OkHttpClient.Builder()
    .dns(object : Dns {
      override fun lookup(hostname: String) =
          InetAddress.getAllByName(hostname).toList()
    })
    .build()
```

SAM conversion impacts these APIs:

 * Authenticator
 * Dispatcher.setIdleCallback(Runnable)

        if (socketHost.canParseAsIpAddress()) {
          listOf(InetAddress.getByName(socketHost))
        } else {
          connectionUser.dnsStart(socketHost)

          val result = address.dns.lookup(socketHost)
          if (result.isEmpty()) {
            throw UnknownHostException("${address.dns} returned no addresses for $socketHost")
          }

          connectionUser.dnsEnd(socketHost, result)

  @get:JvmName("resolvePrivateAddresses") val resolvePrivateAddresses: Boolean,
  @get:JvmName("resolvePublicAddresses") val resolvePublicAddresses: Boolean,
) : Dns {
  @Throws(UnknownHostException::class)
  override fun lookup(hostname: String): List<InetAddress> {
    if (!resolvePrivateAddresses || !resolvePublicAddresses) {
      val privateHost = isPrivateHost(hostname)

      if (privateHost && !resolvePrivateAddresses) {

         * than a handful of exceptions. But it seems prudent to set a cap on how many we'll cache.
         * This avoids out-of-control memory consumption, and it keeps the cache from growing so
         * large that doing the lookup is noticeably slower than redoing the work would be.
         *
         * Ideally we'd have a real eviction policy, but until we see a problem in practice, I hope

        // Default constructor
    }

    private static final Logger logger = LogManager.getLogger(QueryProcessor.class);

    /**
     * Map of query commands indexed by query class simple names.
     * Used to lookup appropriate command handlers for different query types.
     */
    protected Map<String, QueryCommand> queryCommandMap = new HashMap<>();

    /**
     * List of filters that will be applied during query processing.

        scriptEngineFactory.add("name1", engine1);
        scriptEngineFactory.add("name2", engine2);

        // Both engines have same class name, so second should replace first for class name lookup
        ScriptEngine retrievedByClass = scriptEngineFactory.getScriptEngine("testscriptengine");
        assertEquals(engine2, retrievedByClass);

        // But original names should still work

         * than a handful of exceptions. But it seems prudent to set a cap on how many we'll cache.
         * This avoids out-of-control memory consumption, and it keeps the cache from growing so
         * large that doing the lookup is noticeably slower than redoing the work would be.
         *
         * Ideally we'd have a real eviction policy, but until we see a problem in practice, I hope

    public void test_getDataStore_nullName() {
        DataStore retrieved = dataStoreFactory.getDataStore(null);
        assertNull(retrieved);
    }

    // Test getDataStore with case insensitive lookup
    public void test_getDataStore_caseInsensitive() {
        TestDataStore dataStore = new TestDataStore("TestStore");
        dataStoreFactory.add("MyStore", dataStore);