ensureNotDirectlyModifiable(unmod.headSet(2));
    ensureNotDirectlyModifiable(unmod.headSet(2, true));
    ensureNotDirectlyModifiable(unmod.tailSet(2));
    ensureNotDirectlyModifiable(unmod.tailSet(2, true));
    ensureNotDirectlyModifiable(unmod.subSet(1, 3));
    ensureNotDirectlyModifiable(unmod.subSet(1, true, 3, true));

    /* UnsupportedOperationException on indirect modifications. */

 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // we're overriding default serialization
@ElementTypesAreNonnullByDefault
public abstract class ImmutableMultiset<E> extends ImmutableMultisetGwtSerializationDependencies<E>

        if (method.getDeclaringClass().equals(TypeVariableImpl.class)) {
          try {
            method.setAccessible(true);
          } catch (AccessControlException e) {
            // OK: the method is accessible to us anyway. The setAccessible call is only for
            // unusual execution environments where that might not be true.
          }
          builder.put(method.getName(), method);
        }
      }

import com.google.common.testing.SerializableTester;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Test cases for {@link HashBasedTable}.
 *
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class HashBasedTableTest extends AbstractTableTest<Character> {

  @Override
  protected Table<String, Integer, Character> create(@Nullable Object... data) {

import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link MultimapBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class MultimapBuilderTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // doesn't build without explicit type parameters on build() methods

    Object newValue = new Object();

    // no entry
    assertEquals(0, segment.count);
    assertNull(segment.put(key, hash, oldValue, true));
    assertEquals(1, segment.count);

    // same key
    assertSame(oldValue, segment.put(key, hash, newValue, true));
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));

    // cleared

    Object newValue = new Object();

    // no entry
    assertEquals(0, segment.count);
    assertNull(segment.put(key, hash, oldValue, true));
    assertEquals(1, segment.count);

    // same key
    assertSame(oldValue, segment.put(key, hash, newValue, true));
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));

    // cleared

 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multiset">{@code Multiset}</a>.
 *
 * @author Louis Wasserman
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public final class TreeMultiset<E extends @Nullable Object> extends AbstractSortedMultiset<E>
    implements Serializable {

  /**

/**
 * Base class for {@link ImmutableSet} and {@link ImmutableSortedSet} tests.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public abstract class AbstractImmutableSetTest extends TestCase {

  protected abstract <E extends Comparable<? super E>> Set<E> of();

/**
 * Base class for {@link ImmutableSet} and {@link ImmutableSortedSet} tests.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public abstract class AbstractImmutableSetTest extends TestCase {

  protected abstract <E extends Comparable<? super E>> Set<E> of();