Set<K> ks = keySet;
    return (ks != null) ? ks : (keySet = new KeySet(this));
  }

  Collection<V> values;

  @Override
  public Collection<V> values() {
    // does not impact recency ordering
    Collection<V> vs = values;
    return (vs != null) ? vs : (values = new Values(this));
  }

  Set<Entry<K, V>> entrySet;

  @Override
  public Set<Entry<K, V>> entrySet() {

            final String key = "frontmatter." + entry.getKey();
            final List<String> values = entry.getValue();
            if (values != null && !values.isEmpty()) {
                extractData.putValues(key, values.toArray(new String[0]));
            }
        }
    }

    /**
     * Extracts heading text from the document.
     *

  private static final short GREATEST = Short.MAX_VALUE;

  private static final short[] VALUES = {LEAST, (short) -1, (short) 0, (short) 1, GREATEST};

  // We need to test that our method behaves like the JDK method.
  @SuppressWarnings("InlineMeInliner")
  public void testHashCode() {
    for (short value : VALUES) {
      assertThat(Shorts.hashCode(value)).isEqualTo(Short.hashCode(value));
    }
  }

  /**
   * Returns a collection that simulates concurrent modification by having its size method return
   * incorrect values. This is useful for testing methods that must treat the return value from
   * size() as a hint only.
   *
   * @param delta the difference between the true size of the collection and the values returned by
   *     the size method
   */

        entries.add(mapEntry(k, v));
      }
      Iterable<Entry<K, V>> orderedEntries = multimapGenerator.order(entries);
      List<V> values = new ArrayList<>();
      for (Entry<K, V> entry : orderedEntries) {
        values.add(entry.getValue());
      }
      return values;
    }

    @Override
    public Collection<V> create(Object... elements) {

  public void testPutTwoElements() {
    int size = getNumElements();

    List<V> values = copyToList(multimap().get(k0()));

    assertTrue(multimap().put(k0(), v1()));
    assertTrue(multimap().put(k0(), v2()));

    values.add(v1());
    values.add(v2());

    assertGet(k0(), values);
    assertEquals(size + 2, multimap().size());
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})

     */
    public Collection<ChannelInfo> getChannels() {
        return channels.values();
    }

    /**
     * Get healthy channels only
     *
     * @return collection of healthy channels
     */
    public Collection<ChannelInfo> getHealthyChannels() {
        return channels.values()
                .stream()
                .filter(ChannelInfo::isHealthy)

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.TreeMap;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;

/**
 * Utility class for easily creating and setting values in {@link Map} instances.
 * <p>
 * By statically importing this class, you can easily initialize {@literal Map} instances as follows:
 * </p>
 *
 * <pre>
 * import static org.codelibs.core.collection.Maps.*;
 *

    private static final String VALID_UUID_STRING = "00112233-4455-6677-8899-AABBCCDDEEFF";
    private static final String VALID_UUID_STRING_LOWERCASE = "00112233-4455-6677-8899-aabbccddeeff";

    // Corresponding values for the valid UUID string
    private static final int TIME_LOW = 0x00112233;
    private static final short TIME_MID = (short) 0x4455;
    private static final short TIME_HI_AND_VERSION = (short) 0x6677;

    SerializableTester.reserializeAndAssert(map.entrySet());
    SerializableTester.reserializeAndAssert(map.keySet());
    assertEquals(
        new ArrayList<>(map.values()),
        new ArrayList<>(SerializableTester.reserialize(map.values())));
  }