import java.util.concurrent.Callable;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An abstract {@code ScheduledExecutorService} that allows subclasses to {@linkplain
 * #wrapTask(Callable) wrap} tasks before they are submitted to the underlying executor.
 *

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionSize;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Generator for collection of a particular size.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import java.util.SortedSet;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A sorted set multimap which forwards all its method calls to another sorted set multimap.
 * Subclasses should override one or more methods to modify the behavior of the backing multimap as

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Predicate;
import java.util.Map.Entry;
import java.util.Set;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(SetMultimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

 * limitations under the License.
 */

package com.google.common.collect;

import java.util.Collection;
import java.util.List;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * GWT emulated version of {@link ImmutableList}. TODO(cpovirk): more doc
 *
 * @author Hayward Chan
 */
@ElementTypesAreNonnullByDefault

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible(serializable = true, emulated = true)

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

/** An ordering that tries several comparators in order. */
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
final class CompoundOrdering<T extends @Nullable Object> extends Ordering<T>
    implements Serializable {
  final Comparator<? super T>[] comparators;

  @SuppressWarnings("unchecked") // Generic array creation

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

/** An ordering that tries several comparators in order. */
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
final class CompoundOrdering<T extends @Nullable Object> extends Ordering<T>
    implements Serializable {
  final Comparator<? super T>[] comparators;

  @SuppressWarnings("unchecked") // Generic array creation

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible(serializable = true, emulated = true)

 */

package com.google.common.collect;

import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A class that implements {@code Comparable} without generics, such as those found in libraries
 * that support Java 1.4 and before. Our library needs to do the bare minimum to accommodate such