code: public static <K, V> CacheEvent<K, V> update(K key, V oldValue, V newValue, Cache<K, V> source) {
      return new UpdateEvent<>(key, oldValue, newValue, source);
    }
docs: Creates an {@link EventType#UPDATED updated} {@link CacheEvent}.
  
  @param key the key for which the mapping was updated
  @param oldValue the old value
  @param newValue the new value
  @param source the event source
  @param <K> the key type
  @param <V> the value type
  
  @return an updated cache event