verifyHostname(hostname, it)
    }
  }

  /**
   * This is like [toLowerCase] except that it does nothing if this contains any non-ASCII
   * characters. We want to avoid lower casing special chars like U+212A (Kelvin symbol) because
   * they can return ASCII characters that match real hostnames.
   */
  private fun String.asciiToLowercase(): String {
    return when {
      isAscii() -> lowercase(Locale.US) // This is an ASCII string.

import static org.junit.Assert.assertThrows;

import java.io.IOException;
import java.nio.CharBuffer;
import junit.framework.TestCase;

/**
 * Tests for {@link CharSequenceReader}.
 *
 * @author Colin Decker
 */
public class CharSequenceReaderTest extends TestCase {

  public void testReadEmptyString() throws IOException {
    assertReadsCorrectly("");
  }

/**
 * A generator of {@code TestSuite} instances for testing {@code CharSource} implementations.
 * Generates tests of all methods on a {@code CharSource} given various inputs the source is
 * expected to contain.
 *
 * @author Colin Decker
 */
@AndroidIncompatible // TODO(b/230620681): Make this available (even though we won't run it).
public class CharSourceTester extends SourceSinkTester<CharSource, String, CharSourceFactory> {

import java.util.logging.Logger;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Base test case class for I/O tests.
 *
 * @author Chris Nokleberg
 * @author Colin Decker
 */
public abstract class IoTestCase extends TestCase {

  private static final Logger logger = Logger.getLogger(IoTestCase.class.getName());

  static final String I18N =

 * Closeable}. A {@link java.io.Reader} implements both of those interfaces. Similarly for {@code
 * Appendable & Closeable} and {@link java.io.Writer}.
 *
 * @author Chris Nokleberg
 * @author Bin Zhu
 * @author Colin Decker
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class CharStreams {

  // 2K chars (4K bytes)
  private static final int DEFAULT_BUF_SIZE = 0x800;

import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.logging.Logger;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * {@link SourceSinkFactory} implementations.
 *
 * @author Colin Decker
 */
public class SourceSinkFactories {

  private SourceSinkFactories() {}

  public static CharSourceFactory stringCharSourceFactory() {
    return new StringSourceFactory();
  }

 * controls the order in which events are dispatched, while the executor controls how (i.e. on which
 * thread) the subscriber is actually called when an event is dispatched to it.
 *
 * @author Colin Decker
 */
@ElementTypesAreNonnullByDefault
abstract class Dispatcher {

  /**
   * Returns a dispatcher that queues events that are posted reentrantly on a thread that is already

import java.util.EnumSet;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for the default implementations of {@code ByteSource} methods.
 *
 * @author Colin Decker
 */
public class ByteSourceTest extends IoTestCase {

  @AndroidIncompatible // Android doesn't understand suites whose tests lack default constructors.
  public static TestSuite suite() {

You can define dependencies that in turn can define dependencies themselves.

In the end, a hierarchical tree of dependencies is built, and the **Dependency Injection** system takes care of solving all these dependencies for you (and their sub-dependencies) and providing (injecting) the results at each step.

For example, let's say you have 4 API endpoints (*path operations*):

* `/items/public/`

 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/PrimitivesExplained#unsigned-support">unsigned
 * primitive utilities</a>.
 *
 * @author Louis Wasserman
 * @author Colin Evans
 * @since 11.0
 */
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
public final class UnsignedLong extends Number implements Comparable<UnsignedLong>, Serializable {