NavigableMap<String, String> map = populate(new TreeMap<String, String>(), entries);
                return Collections.checkedNavigableMap(map, String.class, String.class);
              }
            })
        .named("checkedNavigableMap/TreeMap, natural")
        .withFeatures(
            MapFeature.GENERAL_PURPOSE,
            MapFeature.ALLOWS_NULL_VALUES,

    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().removeAll(null) doesn't throws NPE.
    }
  }

  @Override
  public void testEntrySetRetainAllNullFromEmpty() {
    try {
      super.testEntrySetRetainAllNullFromEmpty();
    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().retainAll(null) doesn't throws NPE.
    }
  }

  @Override

                SortedMap<String, String> map = populate(new TreeMap<String, String>(), entries);
                return Collections.checkedSortedMap(map, String.class, String.class);
              }
            })
        .named("checkedSortedMap/TreeMap, natural")
        .withFeatures(
            MapFeature.GENERAL_PURPOSE,
            MapFeature.ALLOWS_NULL_VALUES,

    }

    /**
     * {@link TreeMap}の新しいインスタンスを作成して返します。
     *
     * @param <K>
     *            {@link TreeMap}のキーの型
     * @param <V>
     *            {@link TreeMap}の値の型
     * @return {@link TreeMap}の新しいインスタンス
     * @see TreeMap#TreeMap()
     */
    public static <K, V> TreeMap<K, V> newTreeMap() {
        return new TreeMap<>();
    }

    /**

  private static class Factory<C, V> implements Supplier<TreeMap<C, V>>, Serializable {
    final Comparator<? super C> comparator;

    Factory(Comparator<? super C> comparator) {
      this.comparator = comparator;
    }

    @Override
    public TreeMap<C, V> get() {
      return new TreeMap<>(comparator);
    }

    private static final long serialVersionUID = 0;
  }

  /**

import com.google.common.base.Preconditions;
import java.util.Collection;
import java.util.Comparator;
import java.util.EnumMap;
import java.util.EnumSet;
import java.util.LinkedHashMap;
import java.util.TreeMap;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.function.ToIntFunction;
import java.util.stream.Collector;

      K key, @Nullable V value) {
    return generateTreeMap(key, value);
  }

  @Generates
  static <K extends Comparable<? super K>, V> TreeMap<K, V> generateTreeMap(
      K key, @Nullable V value) {
    TreeMap<K, V> map = Maps.newTreeMap();
    map.put(key, value);
    return map;
  }

  @Generates

public class SortedIterablesTest extends TestCase {
  public void testSameComparator() {
    assertTrue(SortedIterables.hasSameComparator(Ordering.natural(), Sets.newTreeSet()));
    // Before JDK6 (including under GWT), the TreeMap keySet is a plain Set.
    if (Maps.newTreeMap().keySet() instanceof SortedSet) {
      assertTrue(SortedIterables.hasSameComparator(Ordering.natural(), Maps.newTreeMap().keySet()));
    }
    assertTrue(

    return getMap().put(entry.getKey(), entry.getValue());
  }

  /**
   * Returns the {@link Method} instance for {@link #testPut_nullKeyUnsupported()} so that tests of
   * {@link java.util.TreeMap} can suppress it with {@code
   * FeatureSpecificTestSuiteBuilder.suppressing()} until <a
   * href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5045147">Sun bug 5045147</a> is fixed.
   */
  @J2ktIncompatible

    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().removeAll(null) doesn't throws NPE.
    }
  }

  @Override
  public void testEntrySetRetainAllNullFromEmpty() {
    try {
      super.testEntrySetRetainAllNullFromEmpty();
    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().retainAll(null) doesn't throws NPE.
    }
  }

  @Override