/* * Copyright (C) 2015 José Paumard * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.paumard.spliterators; import org.paumard.spliterators.util.TryAdvanceCheckingSpliterator; import org.paumard.streams.StreamsUtils; import org.testng.annotations.Test; import java.util.*; import java.util.concurrent.atomic.AtomicInteger; import java.util.function.Function; import java.util.function.Predicate; import java.util.stream.Collectors; import java.util.stream.Stream; import java.util.stream.StreamSupport; import static org.assertj.core.api.Assertions.assertThat; import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException; import static org.assertj.core.api.Assertions.assertThatNullPointerException; /** * Created by José */ public class TraversingSpliteratorTest { @Test public void should_a_return_stream_of_empty_stream_if_provided_streams_are_empty() { // Given // a trick to create an empty ORDERED stream Stream<String> streamA = Stream.of("one").filter(String::isEmpty); Stream<String> streamB = Stream.of("one").filter(String::isEmpty); // When Stream<Stream<String>> traversingStream = StreamsUtils.traverse(streamA, streamB); // Then List<List<String>> collect = traversingStream.map(str -> str.collect(Collectors.toList())) .collect(Collectors.toList()); assertThat(collect.size()).isEqualTo(1); assertThat(collect.get(0)).isEmpty(); } @Test public void should_traverse_two_streams_into_a_traversed_stream() { // Given Stream<String> streamA = Stream.of("a1", "a2", "a3"); Stream<String> streamB = Stream.of("b1", "b2", "b3"); // When Stream<Stream<String>> traversingStream = StreamsUtils.traverse(streamA, streamB); // Then List<List<String>> strings = traversingStream.map(str -> str.collect(Collectors.toList())) .collect(Collectors.toList()); assertThat(strings.size()).isEqualTo(3); assertThat(strings.get(0)).containsSequence("a1", "b1"); assertThat(strings.get(1)).containsSequence("a2", "b2"); assertThat(strings.get(2)).containsSequence("a3", "b3"); } @Test public void should_traverse_two_streams_and_skip_elements_if_a_stream_is_longer_than_the_other() { // Given Stream<String> streamA = Stream.of("a1", "a2"); Stream<String> streamB = Stream.of("b1", "b2", "b3"); // When Stream<Stream<String>> traversingStream = StreamsUtils.traverse(streamA, streamB); // Then List<List<String>> strings = traversingStream.map(str -> str.collect(Collectors.toList())) .collect(Collectors.toList()); assertThat(strings.size()).isEqualTo(2); assertThat(strings.get(0)).containsExactly("a1", "b1"); assertThat(strings.get(1)).containsExactly("a2", "b2"); } @Test public void should_two_sorted_streams_correctly_and_in_an_unsorted_stream() { // Given Stream<String> streamA = new TreeSet<>(Arrays.asList("a", "b", "c")).stream(); Stream<String> streamB = new TreeSet<>(Arrays.asList("0", "1", "2")).stream(); // When Stream<Stream<String>> stream = StreamsUtils.traverse(streamA, streamB); // Then assertThat(stream.spliterator().characteristics() & Spliterator.SORTED).isEqualTo(0); } @Test public void should_conform_to_specified_trySplit_behavior() { // Given Stream<String> streamA = Stream.of("a1", "a2", "a3"); Stream<String> streamB = Stream.of("b1", "b2", "b3"); Stream<Stream<String>> testedStream = StreamsUtils.traverse(streamA, streamB); TryAdvanceCheckingSpliterator<Stream<String>> spliterator = new TryAdvanceCheckingSpliterator<>(testedStream.spliterator()); Stream<String> monitoredStream = StreamSupport.stream(spliterator, false).flatMap(Function.identity()); // When long count = monitoredStream.count(); // Then assertThat(count).isEqualTo(6L); } @Test public void should_correctly_call_the_onClose_callbacks_of_the_underlying_streams() { // Given AtomicInteger i = new AtomicInteger(0); Stream<String> streamA = Stream.of("a1", "a2", "a3").onClose(i::incrementAndGet); Stream<String> streamB = Stream.of("b1", "b2", "b3").onClose(i::incrementAndGet); // When StreamsUtils.traverse(streamA, streamB).close(); // Then assertThat(i.get()).isEqualTo(2); } @Test public void should_correctly_count_the_elements_of_a_sized_stream_for_same_length_streams() { // Given Stream<String> streamA = Stream.of("a1", "a2", "a3"); Stream<String> streamB = Stream.of("b1", "b2", "b3"); Stream<Stream<String>> stream = StreamsUtils.traverse(streamA, streamB); // When long count = stream.count(); // Then assertThat(count).isEqualTo(3L); } @Test public void should_correctly_count_the_elements_of_a_sized_stream_for_different_length_streams() { // Given Stream<String> streamA = Stream.of("a1", "a2", "a3"); Stream<String> streamB = Stream.of("b1", "b2", "b3", "b4"); Stream<Stream<String>> stream = StreamsUtils.traverse(streamA, streamB); // When long count = stream.count(); // Then assertThat(count).isEqualTo(3L); } @Test public void should_not_build_a_transversal_spliterator_on_a_null_spliterator() { // Then assertThatNullPointerException().isThrownBy(() -> StreamsUtils.traverse(null)); } @Test public void should_not_build_a_transversal_spliterator_on_only_one_spliterator() { // Given Stream<String> streamA = Stream.of("a1", "a2"); // When assertThatIllegalArgumentException().isThrownBy(() -> StreamsUtils.traverse(streamA)); } @Test public void should_not_build_a_traversing_spliterator_on_a_non_ordered_stream() { // Given Stream<String> stringsA = Set.of("one", "two").stream(); Stream<String> stringsB = Stream.of("one", "two"); // When assertThatIllegalArgumentException().isThrownBy(() -> StreamsUtils.traverse(stringsA, stringsB)); } }