while (!source.exhausted()) {
          var rule: ByteString = source.readUtf8LineStrict().toRule() ?: continue

          if (rule.startsWith(EXCEPTION_RULE_MARKER)) {
            rule = rule.substring(1)
            // We use '\n' for end of value.
            totalExceptionRuleBytes += rule.size + 1
            sortedExceptionRules.add(rule)
          } else {
            totalRuleBytes += rule.size + 1 // We use '\n' for end of value.

internal fun String.containsInvalidHostnameAsciiCodes(): Boolean {
  for (i in 0 until length) {
    val c = this[i]
    // The WHATWG Host parsing rules accepts some character codes which are invalid by
    // definition for OkHttp's host header checks (and the WHATWG Host syntax definition). Here
    // we rule out characters that would cause problems in host headers.
    if (c <= '\u001f' || c >= '\u007f') {
      return true
    }

import mockwebserver3.MockWebServer
import okhttp3.ExperimentalOkHttpApi
import org.junit.rules.ExternalResource

/**
 * Runs MockWebServer for the duration of a single test method.
 *
 * In Java JUnit 4 tests (ie. tests annotated `@org.junit.Test`), use this by defining a field with
 * the `@Rule` annotation:
 *
 * ```java
 * @Rule public final MockWebServerRule serverRule = new MockWebServerRule();
 * ```
 *

    val rule = findMatchingRule(domainLabels)
    if (domainLabels.size == rule.size && rule[0][0] != EXCEPTION_MARKER) {
      return null // The domain is a public suffix.
    }

    val firstLabelOffset =
      if (rule[0][0] == EXCEPTION_MARKER) {
        // Exception rules hold the effective TLD plus one.
        domainLabels.size - rule.size
      } else {

```
@Rule public final MockWebServerRule serverRule = new MockWebServerRule();
```

The `serverRule` field has a `server` field. It is an instance of `MockWebServer`. That instance
will be shut down automatically after the test runs.

For Kotlin, the `@JvmField` annotation is also necessary:

```
@JvmField @Rule val serverRule = MockWebServerRule()

class MockWebServerRuleTest {
  @Test fun statementStartsAndStops() {
    val rule = MockWebServerRule()
    val called = AtomicBoolean()
    val statement: Statement =
      rule.apply(
        object : Statement() {
          override fun evaluate() {
            called.set(true)
            rule.server.url("/").toUrl().openConnection().connect()
          }
        },
        Description.EMPTY,
      )

import org.junit.AssumptionViolatedException
import org.junit.Before
import org.junit.Ignore
import org.junit.Rule
import org.junit.Test

/**
 * Run with "./gradlew :android-test:connectedCheck -PandroidBuild=true" and make sure ANDROID_SDK_ROOT is set.
 */
class AndroidAsyncDnsTest {
  @JvmField @Rule
  val serverRule = MockWebServerRule()
  private lateinit var client: OkHttpClient

Similarly, the reader thread must never block on writing because this can deadlock the connection. Consider a client and server that both violate this rule. If you get unlucky, they could fill up their TCP buffers (so that writes block) and then use their reader threads to write a frame. Nobody is reading on either end, and the buffers are never drained.

#### Do-stuff-later pool

public final class mockwebserver3/junit4/MockWebServerRule : org/junit/rules/ExternalResource {
	public static final field Companion Lmockwebserver3/junit4/MockWebServerRule$Companion;
	public fun <init> ()V
	public final fun getServer ()Lmockwebserver3/MockWebServer;
}

public final class mockwebserver3/junit4/MockWebServerRule$Companion {

 *
 * This implementation is optimized for readability over efficiency.
 *
 * This implements non-transitional processing by preserving deviation characters.
 *
 * This implementation's STD3 rules are configured to `UseSTD3ASCIIRules=false`. This is
 * permissive and permits the `_` character.
 *
 * [mapping table]: https://www.unicode.org/reports/tr46/#IDNA_Mapping_Table