* the License.
 */

package com.google.common.annotations;

/**
 * Annotates a program element that exists, or is more widely visible than otherwise necessary, only
 * for use in test code.
 *
 * <p><b>Do not use this interface</b> for public or protected declarations: it is a fig leaf for

 * Contains constant definitions for the six standard {@link Charset} instances, which are
 * guaranteed to be supported by all Java platform implementations.
 *
 * <p>Assuming you're free to choose, note that <b>{@link #UTF_8} is widely preferred</b>.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/StringsExplained#charsets">{@code Charsets}</a>.
 *
 * @author Mike Bostock
 * @since 1.0
 */

      return;
    }

    Set<Entry<K, V>> entrySet = map.entrySet();
    if (supportsRemove) {
      try {
        entrySet.retainAll(null);
        // Returning successfully is not ideal, but tolerated.
      } catch (NullPointerException tolerated) {
      }
    } else {
      try {
        entrySet.retainAll(null);
        // We have to tolerate a successful return (Sun bug 4802647)

  @CollectionSize.Require(ZERO)
  public void testRemoveAll_nullCollectionReferenceEmptySubject() {
    try {
      collection.removeAll(null);
      // Returning successfully is not ideal, but tolerated.
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)

import com.google.common.collect.testing.SampleElements.Unhashables;
import java.util.Collection;
import java.util.List;

/**
 * Creates collections containing unhashable sample elements, to be tested.
 *
 * @author Regina O'Dell
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestUnhashableCollectionGenerator<T extends Collection<UnhashableObject>>
    implements TestCollectionGenerator<UnhashableObject> {
  @Override

import com.google.common.collect.testing.SampleElements.Unhashables;
import java.util.Collection;
import java.util.List;

/**
 * Creates collections containing unhashable sample elements, to be tested.
 *
 * @author Regina O'Dell
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestUnhashableCollectionGenerator<T extends Collection<UnhashableObject>>
    implements TestCollectionGenerator<UnhashableObject> {
  @Override

  @CollectionSize.Require(ZERO)
  public void testRetainAll_nullCollectionReferenceEmptySubject() {
    try {
      collection.retainAll(null);
      // Returning successfully is not ideal, but tolerated.
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)

 * relying on any specific Set implementations. Slow. Explicitly allows null elements so that they
 * can be used in the testers.
 *
 * @author Regina O'Dell
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class MinimalSet<E extends @Nullable Object> extends MinimalCollection<E> implements Set<E> {

  @SuppressWarnings("unchecked") // empty Object[] as E[]

 * relying on any specific Set implementations. Slow. Explicitly allows null elements so that they
 * can be used in the testers.
 *
 * @author Regina O'Dell
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class MinimalSet<E extends @Nullable Object> extends MinimalCollection<E> implements Set<E> {

  @SuppressWarnings("unchecked") // empty Object[] as E[]

  @CollectionSize.Require(ZERO)
  public void testRetainAll_nullCollectionReferenceEmptySubject() {
    try {
      collection.retainAll(null);
      // Returning successfully is not ideal, but tolerated.
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)