default:
        return new RegularImmutableAsList<E>(this, toArray());
    }
  }

  /** If this collection is backed by an array of its elements in insertion order, returns it. */
  Object @Nullable [] internalArray() {
    return null;
  }

  /**
   * If this collection is backed by an array of its elements in insertion order, returns the offset
   * where this collection's elements start.
   */

/**
 * Implementation of ImmutableMap backed by a JDK HashMap, which has smartness protecting against
 * hash flooding.
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class JdkBackedImmutableMap<K, V> extends ImmutableMap<K, V> {
  /**
   * Creates an {@code ImmutableMap} backed by a JDK HashMap. Used when probable hash flooding is

    boolean reentrant = lock.isHeldByCurrentThread();
    long startTime = 0L;

    locked:
    {
      if (!fair) {
        // Check interrupt status to get behavior consistent with fair case.
        if (Thread.interrupted()) {
          throw new InterruptedException();
        }
        if (lock.tryLock()) {
          break locked;
        }
      }
      startTime = initNanoTime(timeoutNanos);

import java.util.EnumMap;
import java.util.HashMap;
import java.util.Map;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@code BiMap} backed by an {@code EnumMap} instance for keys-to-values, and a {@code HashMap}
 * instance for values-to-keys. Null keys are not permitted, but null values are. An {@code
 * EnumHashBiMap} and its inverse are both serializable.
 *

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.DoNotCall;
import java.util.Map;
import javax.annotation.CheckForNull;

/**
 * A type-to-instance map backed by an {@link ImmutableMap}. See also {@link
 * MutableTypeToInstanceMap}.
 *
 * @author Ben Yu
 * @since 13.0
 */
@ElementTypesAreNonnullByDefault

   * calling thread. Tasks are run to completion before a {@code Future} is returned to the caller
   * (unless the executor has been shutdown).
   *
   * <p>The returned executor is backed by the executor returned by {@link
   * MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *
   * <p>Although all tasks are immediately executed in the thread that submitted the task, this

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.EnumMap;
import java.util.Map;

/**
 * A {@code BiMap} backed by two {@code EnumMap} instances. Null keys and values are not permitted.
 * An {@code EnumBiMap} and its inverse are both serializable.
 *
 * <p>See the Guava User Guide article on <a href=

   * state: BLOCKED, WAITING, or TIMED_WAITING.
   */
  void waitForThreadToEnterWaitState(Thread thread, long timeoutMillis) {
    long startTime = System.nanoTime();
    for (; ; ) {
      Thread.State s = thread.getState();
      if (s == Thread.State.BLOCKED || s == Thread.State.WAITING || s == Thread.State.TIMED_WAITING)
        return;

    }
    this.cellRowIndices = cellRowIndices;
    this.cellColumnIndices = cellColumnIndices;
    this.rowMap = new RowMap();
    this.columnMap = new ColumnMap();
  }

  /** An immutable map implementation backed by an indexed nullable array. */
  private abstract static class ImmutableArrayMap<K, V> extends IteratorBasedImmutableMap<K, V> {
    private final int size;

    ImmutableArrayMap(int size) {
      this.size = size;

    sendRequest(methodName, arguments);
    assertEquals(expected, getResponse(methodName).getThrowable().getClass());
  }

  /**
   * Causes this thread to call the named method, and asserts that this thread becomes blocked on
   * the lock-like object. The lock-like object must have a method equivalent to {@link
   * java.util.concurrent.locks.ReentrantLock#hasQueuedThread(Thread)}.
   */