import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.google.ReflectionFreeAssertThrows.assertThrows;
import static java.util.Arrays.asList;
import static java.util.Collections.singleton;

import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.google.ReflectionFreeAssertThrows.assertThrows;
import static java.util.Arrays.asList;
import static java.util.Collections.singleton;

@NullMarked
public class JoinerTest extends TestCase {
  private static final Joiner J = Joiner.on("-");

  // <Integer> needed to prevent warning :(
  private static final Iterable<Integer> iterable = Arrays.<Integer>asList();
  private static final Iterable<Integer> iterable1 = Arrays.asList(1);
  private static final Iterable<Integer> iterable12 = Arrays.asList(1, 2);
  private static final Iterable<Integer> iterable123 = Arrays.asList(1, 2, 3);

 */

package com.google.common.io;

import static com.google.common.base.StandardSystemProperty.OS_NAME;
import static com.google.common.io.RecursiveDeleteOption.ALLOW_INSECURE;
import static com.google.common.jimfs.Feature.SECURE_DIRECTORY_STREAM;
import static com.google.common.jimfs.Feature.SYMBOLIC_LINKS;
import static com.google.common.truth.Truth.assertThat;
import static java.nio.charset.StandardCharsets.UTF_8;

 * the License.
 */

package com.google.common.primitives;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkPositionIndexes;
import static java.lang.Long.parseLong;

import com.google.common.annotations.GwtCompatible;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Map;
import org.jspecify.annotations.Nullable;

/**
 * Provides static methods for serializing collection classes.
 *
 * <p>This class assists the implementation of collection classes. Do not use this class to
 * serialize collections that are defined elsewhere.
 *
 * @author Jared Levy
 */

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.truth.Truth.assertThat;
import static java.util.concurrent.Executors.newCachedThreadPool;
import static java.util.concurrent.TimeUnit.SECONDS;
import static junit.framework.Assert.assertEquals;
import static junit.framework.Assert.assertFalse;
import static junit.framework.Assert.assertTrue;

 */

package com.google.common.hash;

import static com.google.common.base.Preconditions.checkPositionIndexes;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.hash.Hashing.GOOD_FAST_HASH_SEED;
import static java.lang.Byte.toUnsignedInt;
import static java.nio.charset.StandardCharsets.UTF_8;

import com.google.common.primitives.Chars;

package com.google.common.io;

import static com.google.common.collect.ImmutableList.toImmutableList;
import static com.google.common.io.TestOption.CLOSE_THROWS;
import static com.google.common.io.TestOption.OPEN_THROWS;
import static com.google.common.io.TestOption.READ_THROWS;
import static com.google.common.io.TestOption.WRITE_THROWS;
import static com.google.common.truth.Truth.assertThat;
import static org.junit.Assert.assertThrows;

    public static final String AFTER_LAST = "z";
    public static final String AFTER_LAST_2 = "zz";
  }

  public static class Chars extends SampleElements<Character> {
    public Chars() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super('b', 'a', 'c', 'd', 'e');
    }
  }

  public static class Enums extends SampleElements<AnEnum> {
    public Enums() {