ImmutableList.Builder<Future<?>> futures = ImmutableList.builder();
    for (int i = 0; i < threadCount; i++) {
      futures.add(
          executor.submit(
              new Callable<@Nullable Void>() {
                @Override
                public @Nullable Void call() throws Exception {
                  barrier.await();
                  Integer first = graph.nodes().iterator().next();

import com.google.errorprone.annotations.DoNotMock;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import java.util.concurrent.RejectedExecutionException;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link Future} that accepts completion listeners. Each listener has an associated executor, and
 * it is invoked using this executor once the future's computation is {@linkplain Future#isDone()

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Static convenience methods that serve the same purpose as Java language <a
 * href="https://docs.oracle.com/javase/8/docs/technotes/guides/language/assert.html">assertions</a>,

import java.util.NoSuchElementException;
import java.util.Set;
import java.util.Spliterator;
import java.util.function.Consumer;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An immutable sorted set with one or more elements. TODO(jlevy): Consider separate class for a
 * single-element sorted set.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */

      long seed, @Nullable Object expected, @Nullable Object actual) {
    if (!equal(actual, expected)) {
      // fail(), but with the JUnit-supplied message.
      assertEquals("Using seed " + seed, expected, actual);
    }
  }

  private static void assertEqualsUsingStartedWith(
      Collection<?> startedWith, @Nullable Object expected, @Nullable Object actual) {
    if (!equal(actual, expected)) {

				alterColumn = true
			}
		}
	}

	// check nullable
	if nullable, ok := columnType.Nullable(); ok && nullable == field.NotNull {
		// not primary key & database is nullable
		if !field.PrimaryKey && nullable {
			alterColumn = true
		}
	}

	// check default value
	if !field.PrimaryKey {

    // that are spec'd to throw CCE and NPE should call this.
    @SuppressWarnings({"unchecked", "nullness"})
    Comparator<@Nullable Object> unsafeComparator = (Comparator<@Nullable Object>) comparator;
    return unsafeComparator.compare(a, b);
  }

  final transient Comparator<? super E> comparator;

  ImmutableSortedSet(Comparator<? super E> comparator) {

import java.util.Map;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collector;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link Table} whose contents will never change, with many other important properties detailed
 * at {@link ImmutableCollection}.
 *
 * <p>See the Guava User Guide article on <a href=

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests common methods in {@link ImmutableTable}
 *
 * @author Gregory Kick
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class ImmutableTableTest extends AbstractTableReadTest<Character> {
  @Override
  protected Table<String, Integer, Character> create(@Nullable Object... data) {

import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link BiMap} whose contents will never change, with many other important properties detailed
 * at {@link ImmutableCollection}.
 *
 * @author Jared Levy
 * @since 2.0
 */