import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.singleton;
import static java.util.Comparator.comparing;
import static java.util.Comparator.naturalOrder;
import static java.util.Comparator.reverseOrder;

import com.google.common.annotations.GwtCompatible;
import com.google.common.testing.EqualsTester;
import java.util.Collections;
import java.util.Comparator;

import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.singleton;
import static java.util.Comparator.comparing;
import static java.util.Comparator.naturalOrder;
import static java.util.Comparator.reverseOrder;

import com.google.common.annotations.GwtCompatible;
import com.google.common.testing.EqualsTester;
import java.util.Collections;
import java.util.Comparator;

    @Override
    public SortedMap<String, String> create(Entry<String, String>[] entries) {
      ImmutableSortedMap.Builder<String, String> builder = ImmutableSortedMap.naturalOrder();
      for (Entry<String, String> entry : entries) {
        checkNotNull(entry);
        builder.put(entry.getKey(), entry.getValue());
      }
      return builder.build();
    }
  }

        .thenComparing(v -> v.minor)
        .thenComparing(v -> v.revision)
        .thenComparing((QualifiedVersion v) -> v.qualifier, Comparator.nullsLast(Comparator.naturalOrder()));

    @Override
    public int compareTo(QualifiedVersion other) {
        return COMPARATOR.compare(this, other);
    }

    public boolean isBefore(QualifiedVersion other) {

                  protected SortedMap<String, String> create(Entry<String, String>[] entries) {
                    ImmutableSortedMap.Builder<String, String> builder =
                        ImmutableSortedMap.naturalOrder();
                    for (Entry<String, String> entry : entries) {
                      builder.put(entry.getKey(), entry.getValue());
                    }

                  protected SortedMap<String, String> create(Entry<String, String>[] entries) {
                    ImmutableSortedMap.Builder<String, String> builder =
                        ImmutableSortedMap.naturalOrder();
                    for (Entry<String, String> entry : entries) {
                      builder.put(entry.getKey(), entry.getValue());
                    }

      }
    },
    ImmutableSorted {
      @Override
      Map<Element, Element> create(Collection<Element> keys) {
        ImmutableSortedMap.Builder<Element, Element> builder = ImmutableSortedMap.naturalOrder();
        for (Element element : keys) {
          builder.put(element, element);
        }
        return builder.build();
      }
    };

 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeSet<E> implements Serializable, NavigableSet<E> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);

  private final NavigableSet<E> delegate;

  public SafeTreeSet() {
    this(new TreeSet<E>());
  }

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class SortedMapNavigationTester<K, V> extends AbstractMapTester<K, V> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);

  private SortedMap<K, V> navigableMap;
  private Entry<K, V> a;
  private Entry<K, V> c;

  @Override
  public void setUp() throws Exception {

 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeMap<K, V> implements Serializable, NavigableMap<K, V> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);

  private final NavigableMap<K, V> delegate;

  public SafeTreeMap() {
    this(new TreeMap<K, V>());
  }