}
        }
        return new String(buf);
    }

    /**
     * ロケールが持つスタイルに対応する{@link DateFormat}を反復する{@link Iterator}です。
     *
     * @author koichik
     */
    protected static class DateFormatIterator implements Iterator<DateFormat> {

        /** ロケール */
        protected final Locale locale;

        /** 現在のスタイルを示すインデックス */
        protected int index;

import com.google.common.collect.testing.features.CollectionSize;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.NavigableSet;
import java.util.TreeSet;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a NavigableSet. Can't be invoked directly; please

    assertThat(stream(Arrays.asList(1, 2, 3)).filter(n -> n > 1)).containsExactly(2, 3);
  }

  public void testStream_iterator() {
    assertThat(stream(Arrays.asList().iterator())).isEmpty();
    assertThat(stream(Arrays.asList("a").iterator())).containsExactly("a");
    assertThat(stream(Arrays.asList(1, 2, 3).iterator()).filter(n -> n > 1)).containsExactly(2, 3);
  }

  public void testStream_googleOptional() {

                // care performance for List that the most frequent pattern
                final Object first = coll instanceof List<?> ? ((List<?>) coll).get(0) : coll.iterator().next();
                if (first instanceof Entity) {
                    data.register(key, coll.stream().map(BeanUtil::copyBeanToNewMap).collect(Collectors.toList()));
                    return;
                }

  E element;

  SingletonImmutableSet(E element) {
    this.element = checkNotNull(element);
  }

  @Override
  public int size() {
    return 1;
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.singletonIterator(element);
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return element.equals(object);
  }

  // Refined Collection Methods

  /**
   * {@inheritDoc}
   *
   * <p>Elements that occur multiple times in the multiset will appear multiple times in this
   * iterator, though not necessarily sequentially.
   */
  @Override
  Iterator<E> iterator();

  /**
   * Determines whether this multiset contains the specified element.
   *

   * <i>only</i> if the caller knows that the collection does not contain any null elements.
   *
   * <p>This method returns the elements in the order they are returned by the collection's
   * iterator.
   *
   * <p>TODO(kevinb): support concurrently modified collections?
   *
   * @param c the collection for which to return an array of elements
   * @param array the array in which to place the collection elements

    return Multisets.immutableEntry(element, count);
  }

  private static <E extends @Nullable Object> Entry<E> control(E element, int count) {
    return HashMultiset.create(Collections.nCopies(count, element)).entrySet().iterator().next();
  }

  public void testToString() {
    assertEquals("foo", entry("foo", 1).toString());
    assertEquals("bar x 2", entry("bar", 2).toString());
  }

  public void testToStringNull() {

  @Override
  public Set<Entry<K, V>> entrySet() {
    Set<Entry<K, V>> es = entrySet;
    return (es != null) ? es : (entrySet = new EntrySet());
  }

  // Iterator Support

  abstract class HashIterator<T> implements Iterator<T> {

    int nextSegmentIndex;
    int nextTableIndex;
    @CheckForNull Segment<K, V, E, S> currentSegment;
    @CheckForNull AtomicReferenceArray<E> currentTable;

      return super.containsAll(c);
    }

    @Override
    public boolean isEmpty() {
      assertTrue(Thread.holdsLock(mutex));
      return super.isEmpty();
    }

    /* Don't test iterator(); it may or may not hold the mutex. */

    @Override
    public boolean remove(@Nullable Object o) {
      assertTrue(Thread.holdsLock(mutex));
      return super.remove(o);
    }

    @Override