### Question:
BigTableEntityAsyncDao extends AbstractDao<T> implements AsyncDao<T> { @Override public <K extends Key<T>> CompletableFuture<Map<K, T>> saveAll(final Map<K, T> entities) throws IOException { Objects.requireNonNull(entities); final PutResultDto<K, T> putResults = entitiesToPuts(entities); final Map<K, T> results = putResults.getKeyValueMap(); final List<Put> puts = putResults.getPuts(); return table.putAll(puts).thenApply(c -> results); } BigTableEntityAsyncDao(final AsyncTable<?> table,
                           final Iterable<? extends Column> columns,
                           final Supplier<T> entityFactory,
                           final Function<T, EntityConfiguration.EntityDelegate<T>> delegateFactory,
                           final ObjectMapper objectMapper);   BigTableEntityAsyncDao(final AsyncTable<?> table,
                           final Iterable<? extends Column> columns,
                           final Supplier<T> entityFactory,
                           final Function<T, EntityConfiguration.EntityDelegate<T>> delegateFactory); @Override CompletableFuture<T> get(final K key); @Override Map<K, CompletableFuture<T>> get(final Set<K> keys); @Override CompletableFuture<Map<K, T>> getAll(final Set<K> keys); @Override CompletableFuture<SortedMap<Key<T>, T>> scan(final K startKey,
                                                                           final boolean startKeyInclusive,
                                                                           final K endKey,
                                                                           final boolean endKeyInclusive,
                                                                           final int numRows); @Override CompletableFuture<SortedMap<Key<T>, T>> scan(final K startKey,
                                                                           final boolean startKeyInclusive,
                                                                           final K endKey,
                                                                           final boolean endKeyInclusive,
                                                                           final int numRows,
                                                                           @Nullable final String constant); @Override CompletableFuture<T> save(final K key, final T entity); @Override Map<K, CompletableFuture<T>> save(final Map<K, T> entities); @Override CompletableFuture<Map<K, T>> saveAll(final Map<K, T> entities); @Override CompletableFuture<Void> delete(final K key); @Override List<CompletableFuture<Void>> delete(final Set<K> keys); @Override CompletableFuture<Void> deleteAll(final Set<K> keys);  }### Answer:
@Test(expected = NullPointerException.class) public void testSaveAllWithNullMapThrowsNullPointerException() throws IOException { testEntityDao.saveAll(null); }