throws IOException {
    if (singleByte) {
      for (int i = off; i < off + len; i++) {
        out.write(b[i]);
      }
    } else {
      out.write(b, off, len);
    }
    out.flush(); // for coverage
  }

  // TODO(chrisn): only works if we ensure we have crossed file threshold

  public void testWriteErrorAfterClose() throws Exception {
    byte[] data = newPreFilledByteArray(100);

import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Pattern;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Generates fresh instances of types that are different from each other (if possible).
 *
 * @author Ben Yu
 */
@GwtIncompatible
@J2ktIncompatible
class FreshValueGenerator {

      Object instance = ArbitraryInstances.get(mutableClass);
      assertNotNull("Expected to return non-null for: " + mutableClass, instance);
      assertNotSame(
          "Expected to return fresh instance for: " + mutableClass,
          instance,
          ArbitraryInstances.get(mutableClass));
    }
  }

  private enum EmptyEnum {}

  private enum Direction {
    UP,
    DOWN
  }

  <T> T serialClone(T o) {
    try {
      ByteArrayOutputStream bos = new ByteArrayOutputStream();
      ObjectOutputStream oos = new ObjectOutputStream(bos);
      oos.writeObject(o);
      oos.flush();
      oos.close();
      ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(bos.toByteArray()));
      T clone = (T) ois.readObject();
      assertSame(o.getClass(), clone.getClass());

      return this;
    }

    @Override
    public Appendable append(CharSequence csq, int start, int end) {
      result.append(csq, start, end);
      return this;
    }

    @Override
    public void flush() {
      flushed = true;
    }

    @Override
    public void close() {
      closed = true;
    }
  }

  public void testWriteMethods() throws IOException {

            writtenChars++;
            bitBufferLength -= alphabet.bitsPerChar;
          }
        }

        @Override
        public void flush() throws IOException {
          out.flush();
        }

        @Override
        public void close() throws IOException {
          if (bitBufferLength > 0) {

    Collection<Integer> values = map.values();

    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    ObjectOutputStream oos = new ObjectOutputStream(bytes);
    oos.writeObject(map);
    oos.flush();

    int mapSize = bytes.size();
    oos.writeObject(keySet);
    oos.writeObject(values);
    oos.close();

    int finalSize = bytes.size();

  <T> T serialClone(T o) {
    try {
      ByteArrayOutputStream bos = new ByteArrayOutputStream();
      ObjectOutputStream oos = new ObjectOutputStream(bos);
      oos.writeObject(o);
      oos.flush();
      oos.close();
      ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(bos.toByteArray()));
      T clone = (T) ois.readObject();
      assertSame(o.getClass(), clone.getClass());

    out.write(b, off, len);
  }

  @Override
  public synchronized void close() throws IOException {
    out.close();
  }

  @Override
  public synchronized void flush() throws IOException {
    out.flush();
  }

  /**
   * Checks if writing {@code len} bytes would go over threshold, and switches to file buffering if
   * so.
   */
  @GuardedBy("this")

 * IteratorTester#newTargetIterator()} method. This is because it's impossible to test an Iterator
 * without changing its state, so the tester needs a steady supply of fresh Iterators.
 *
 * <p>If your iterator supports modification through {@code remove()}, you may wish to override the
 * verify() method, which is called after each sequence and is guaranteed to be called