java.util.stream.TestData#OfRef ( )源码实例Demo

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testSimpleGroupBy(String name, TestData.OfRef<Integer> data) throws ReflectiveOperationException {
    Function<Integer, Integer> classifier = i -> i % 3;

    // Single-level groupBy
    exerciseMapTabulation(data, groupingBy(classifier),
                          new GroupedMapAssertion<>(classifier, HashMap.class,
                                                    new ListAssertion<>()));
    exerciseMapTabulation(data, groupingByConcurrent(classifier),
                          new GroupedMapAssertion<>(classifier, ConcurrentHashMap.class,
                                                    new ListAssertion<>()));

    // With explicit constructors
    exerciseMapTabulation(data,
                          groupingBy(classifier, TreeMap::new, toCollection(HashSet::new)),
                          new GroupedMapAssertion<>(classifier, TreeMap.class,
                                                    new CollectionAssertion<Integer>(HashSet.class, false)));
    exerciseMapTabulation(data,
                          groupingByConcurrent(classifier, ConcurrentSkipListMap::new,
                                               toCollection(HashSet::new)),
                          new GroupedMapAssertion<>(classifier, ConcurrentSkipListMap.class,
                                                    new CollectionAssertion<Integer>(HashSet.class, false)));
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testSimpleGroupBy(String name, TestData.OfRef<Integer> data) throws ReflectiveOperationException {
    Function<Integer, Integer> classifier = i -> i % 3;

    // Single-level groupBy
    exerciseMapTabulation(data, groupingBy(classifier),
                          new GroupedMapAssertion<>(classifier, HashMap.class,
                                                    new ListAssertion<>()));
    exerciseMapTabulation(data, groupingByConcurrent(classifier),
                          new GroupedMapAssertion<>(classifier, ConcurrentHashMap.class,
                                                    new ListAssertion<>()));

    // With explicit constructors
    exerciseMapTabulation(data,
                          groupingBy(classifier, TreeMap::new, toCollection(HashSet::new)),
                          new GroupedMapAssertion<>(classifier, TreeMap.class,
                                                    new CollectionAssertion<Integer>(HashSet.class, false)));
    exerciseMapTabulation(data,
                          groupingByConcurrent(classifier, ConcurrentSkipListMap::new,
                                               toCollection(HashSet::new)),
                          new GroupedMapAssertion<>(classifier, ConcurrentSkipListMap.class,
                                                    new CollectionAssertion<Integer>(HashSet.class, false)));
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
      groups = { "serialization-hostile" })
public void testSkipLimitOps(String name, TestData.OfRef<Integer> data) {
    List<Integer> skips = sizes(data.size());
    List<Integer> limits = skips;

    for (int s : skips) {
        setContext("skip", s);
        for (int l : limits) {
            setContext("limit", l);
            testSliceMulti(data,
                           sliceSize(sliceSize(data.size(), s), 0, l),
                           st -> st.skip(s).limit(l),
                           st -> st.skip(s).limit(l),
                           st -> st.skip(s).limit(l),
                           st -> st.skip(s).limit(l));
        }
    }
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
      groups = { "serialization-hostile" })
public void testSkipOps(String name, TestData.OfRef<Integer> data) {
    List<Integer> skips = sizes(data.size());

    for (int s : skips) {
        setContext("skip", s);
        testSliceMulti(data,
                       sliceSize(data.size(), s),
                       st -> st.skip(s),
                       st -> st.skip(s),
                       st -> st.skip(s),
                       st -> st.skip(s));

        testSliceMulti(data,
                       sliceSize(sliceSize(data.size(), s), s/2),
                       st -> st.skip(s).skip(s / 2),
                       st -> st.skip(s).skip(s / 2),
                       st -> st.skip(s).skip(s / 2),
                       st -> st.skip(s).skip(s / 2));
    }
}
 

List<MapperData<Integer, ?>> getMapperData(TestData.OfRef<Integer> data) {
    int uniqueSize = data.into(new HashSet<>()).size();

    return Arrays.asList(
        new MapperData<>(mId, uniqueSize),
        new MapperData<>(mZero, Math.min(1, data.size())),
        new MapperData<>(mDoubler, uniqueSize),
        new MapperData<>(LambdaTestHelpers.compose(mId, mDoubler), uniqueSize),
        new MapperData<>(LambdaTestHelpers.compose(mDoubler, mDoubler), uniqueSize),

        new MapperData<>(LambdaTestHelpers.forPredicate(pFalse, true, false), Math.min(1, uniqueSize)),
        new MapperData<>(LambdaTestHelpers.forPredicate(pTrue, true, false), Math.min(1, uniqueSize)),
        new MapperData<>(LambdaTestHelpers.forPredicate(pEven, true, false), Math.min(2, uniqueSize)),
        new MapperData<>(LambdaTestHelpers.forPredicate(pOdd, true, false), Math.min(2, uniqueSize))
    );
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testStream(String name, TestData.OfRef<Integer> data) {
    for (Predicate<Integer> p : INTEGER_PREDICATES) {
        setContext("p", p);
        for (Kind kind : Kind.values()) {
            setContext("kind", kind);
            exerciseTerminalOps(data, this.<Integer>kinds().get(kind).apply(p));
            exerciseTerminalOps(data, s -> s.filter(pFalse), this.<Integer>kinds().get(kind).apply(p));
            exerciseTerminalOps(data, s -> s.filter(pEven), this.<Integer>kinds().get(kind).apply(p));
        }
    }
}
 

@SuppressWarnings({"rawtypes", "unchecked"})
@Test(dataProvider = "StreamTestData<Integer>.mini", dataProviderClass = StreamTestDataProvider.class)
public void testMixedSeqPar(String name, TestData.OfRef<Integer> data) {
    Function<Integer, Integer> id = LambdaTestHelpers.identity();
    UnaryOperator<Stream<Integer>>[] changers
            = new UnaryOperator[] {
            (UnaryOperator<Stream<Integer>>) s -> s,
            (UnaryOperator<Stream<Integer>>) s -> s.sequential(),
            (UnaryOperator<Stream<Integer>>) s -> s.parallel(),
            (UnaryOperator<Stream<Integer>>) s -> s.unordered()
    };
    UnaryOperator<Stream<Integer>>[] stuff
            = new UnaryOperator[] {
            (UnaryOperator<Stream<Integer>>) s -> s,
            (UnaryOperator<Stream<Integer>>) s -> s.map(id),
            (UnaryOperator<Stream<Integer>>) s -> s.sorted(Comparator.naturalOrder()),
            (UnaryOperator<Stream<Integer>>) s -> s.map(id).sorted(Comparator.naturalOrder()).map(id),
            (UnaryOperator<Stream<Integer>>) s -> s.filter(LambdaTestHelpers.pEven).sorted(Comparator.naturalOrder()).map(id),
    };

    for (int c1Index = 0; c1Index < changers.length; c1Index++) {
        setContext("c1Index", c1Index);
        UnaryOperator<Stream<Integer>> c1 = changers[c1Index];
        for (int s1Index = 0; s1Index < stuff.length; s1Index++) {
            setContext("s1Index", s1Index);
            UnaryOperator<Stream<Integer>> s1 = stuff[s1Index];
            for (int c2Index = 0; c2Index < changers.length; c2Index++) {
                setContext("c2Index", c2Index);
                UnaryOperator<Stream<Integer>> c2 = changers[c2Index];
                for (int s2Index = 0; s2Index < stuff.length; s2Index++) {
                    setContext("s2Index", s2Index);
                    UnaryOperator<Stream<Integer>> s2 = stuff[s2Index];
                    UnaryOperator<Stream<Integer>> composed = s -> s2.apply(c2.apply(s1.apply(c1.apply(s))));
                    exerciseOps(data, composed);
                }
            }
        }
    }
}
 

@SuppressWarnings({"rawtypes", "unchecked"})
@Test(dataProvider = "StreamTestData<Integer>.mini", dataProviderClass = StreamTestDataProvider.class)
public void testMixedSeqPar(String name, TestData.OfRef<Integer> data) {
    Function<Integer, Integer> id = LambdaTestHelpers.identity();
    UnaryOperator<Stream<Integer>>[] changers
            = new UnaryOperator[] {
            (UnaryOperator<Stream<Integer>>) s -> s,
            (UnaryOperator<Stream<Integer>>) s -> s.sequential(),
            (UnaryOperator<Stream<Integer>>) s -> s.parallel(),
            (UnaryOperator<Stream<Integer>>) s -> s.unordered()
    };
    UnaryOperator<Stream<Integer>>[] stuff
            = new UnaryOperator[] {
            (UnaryOperator<Stream<Integer>>) s -> s,
            (UnaryOperator<Stream<Integer>>) s -> s.map(id),
            (UnaryOperator<Stream<Integer>>) s -> s.sorted(Comparator.naturalOrder()),
            (UnaryOperator<Stream<Integer>>) s -> s.map(id).sorted(Comparator.naturalOrder()).map(id),
            (UnaryOperator<Stream<Integer>>) s -> s.filter(LambdaTestHelpers.pEven).sorted(Comparator.naturalOrder()).map(id),
    };

    for (int c1Index = 0; c1Index < changers.length; c1Index++) {
        setContext("c1Index", c1Index);
        UnaryOperator<Stream<Integer>> c1 = changers[c1Index];
        for (int s1Index = 0; s1Index < stuff.length; s1Index++) {
            setContext("s1Index", s1Index);
            UnaryOperator<Stream<Integer>> s1 = stuff[s1Index];
            for (int c2Index = 0; c2Index < changers.length; c2Index++) {
                setContext("c2Index", c2Index);
                UnaryOperator<Stream<Integer>> c2 = changers[c2Index];
                for (int s2Index = 0; s2Index < stuff.length; s2Index++) {
                    setContext("s2Index", s2Index);
                    UnaryOperator<Stream<Integer>> s2 = stuff[s2Index];
                    UnaryOperator<Stream<Integer>> composed = s -> s2.apply(c2.apply(s1.apply(c1.apply(s))));
                    exerciseOps(data, composed);
                }
            }
        }
    }
}
 

@Test
public void testSingleton() {
    TestData.OfRef<Integer> data = TestData.Factory.ofSupplier("[0, 1)",
                                                               () -> Stream.of(1));

    withData(data).
            stream(s -> s).
            expectedResult(Collections.singletonList(1)).
            exercise();

    withData(data).
            stream(s -> s.map(LambdaTestHelpers.identity())).
            expectedResult(Collections.singletonList(1)).
            exercise();
}
 

@Test(dataProvider = "withNull:StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testOpWithNullSorted(String name, TestData.OfRef<Integer> data) {
    List<Integer> l = new ArrayList<>();
    data.into(l).sort(cNullInteger);
    // Need to inject SORTED into the sorted list source since
    // sorted() with a comparator ironically clears SORTED
    Collection<Integer> node = exerciseOps(new SortedTestData<>(l), Stream::distinct);
    assertUnique(node);
    assertSorted(node, cNullInteger);
}
 

private<T> String join(TestData.OfRef<T> data, String delim) {
    StringBuilder sb = new StringBuilder();
    boolean first = true;
    for (T i : data) {
        if (!first)
            sb.append(delim);
        sb.append(i.toString());
        first = false;
    }
    return sb.toString();
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testSimplePartition(String name, TestData.OfRef<Integer> data) throws ReflectiveOperationException {
    Predicate<Integer> classifier = i -> i % 3 == 0;

    // Single-level partition to downstream List
    exerciseMapTabulation(data,
                          partitioningBy(classifier),
                          new PartitionAssertion<>(classifier, new ListAssertion<>()));
    exerciseMapTabulation(data,
                          partitioningBy(classifier, toList()),
                          new PartitionAssertion<>(classifier, new ListAssertion<>()));
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testOp(String name, TestData.OfRef<Integer> data) {
    Collection<Integer> result = exerciseOpsInt(
            data,
            Stream::distinct,
            IntStream::distinct,
            LongStream::distinct,
            DoubleStream::distinct);

    assertUnique(result);
    assertTrue((data.size() > 0) ? result.size() > 0 : result.size() == 0);
    assertTrue(result.size() <= data.size());
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testDistinctDistinct(String name, TestData.OfRef<Integer> data) {
    Collection<Integer> result = exerciseOpsInt(
            data,
            s -> s.distinct().distinct(),
            s -> s.distinct().distinct(),
            s -> s.distinct().distinct(),
            s -> s.distinct().distinct());

     assertUnique(result);
}
 

private void testSliceMulti(TestData.OfRef<Integer> data,
                            int expectedSize,
                            Function<Stream<Integer>, Stream<Integer>> mRef,
                            Function<IntStream, IntStream> mInt,
                            Function<LongStream, LongStream> mLong,
                            Function<DoubleStream, DoubleStream> mDouble) {

    @SuppressWarnings({ "rawtypes", "unchecked" })
    Function<Stream<Integer>, Stream<Integer>>[] ms = new Function[4];
    ms[0] = mRef;
    ms[1] = s -> mInt.apply(s.mapToInt(e -> e)).mapToObj(e -> e);
    ms[2] = s -> mLong.apply(s.mapToLong(e -> e)).mapToObj(e -> (int) e);
    ms[3] = s -> mDouble.apply(s.mapToDouble(e -> e)).mapToObj(e -> (int) e);
    testSliceMulti(data, expectedSize, ms);
}
 

private TestData.OfRef<Long> refLongs() {
    return refLongRange(0, Long.MAX_VALUE);
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testSpliterators(String name, TestData.OfRef<Integer> data) {
    for (Function<Stream<Integer>, Stream<Integer>> f : streamFunctions()) {
        SpliteratorTestHelper.testSpliterator(() -> f.apply(data.stream()).spliterator());
    }
}
 

private TestData.OfRef<Long> refLongs() {
    return refLongRange(0, Long.MAX_VALUE);
}
 

private<T, R> void assertCollect(TestData.OfRef<T> data,
                                 Collector<T, ?, R> collector,
                                 Function<Stream<T>, R> streamReduction) {
    R check = streamReduction.apply(data.stream());
    withData(data).terminal(s -> s.collect(collector)).expectedResult(check).exercise();
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testJoin(String name, TestData.OfRef<Integer> data) throws ReflectiveOperationException {
    withData(data)
            .terminal(s -> s.map(Object::toString).collect(Collectors.joining()))
            .expectedResult(join(data, ""))
            .exercise();

    Collector<String, StringBuilder, String> likeJoining = Collector.of(StringBuilder::new, StringBuilder::append, (sb1, sb2) -> sb1.append(sb2.toString()), StringBuilder::toString);
    withData(data)
            .terminal(s -> s.map(Object::toString).collect(likeJoining))
            .expectedResult(join(data, ""))
            .exercise();

    withData(data)
            .terminal(s -> s.map(Object::toString).collect(Collectors.joining(",")))
            .expectedResult(join(data, ","))
            .exercise();

    withData(data)
            .terminal(s -> s.map(Object::toString).collect(Collectors.joining(",", "[", "]")))
            .expectedResult("[" + join(data, ",") + "]")
            .exercise();

    withData(data)
            .terminal(s -> s.map(Object::toString)
                            .collect(StringBuilder::new, StringBuilder::append, StringBuilder::append)
                            .toString())
            .expectedResult(join(data, ""))
            .exercise();

    withData(data)
            .terminal(s -> s.map(Object::toString)
                            .collect(() -> new StringJoiner(","),
                                     (sj, cs) -> sj.add(cs),
                                     (j1, j2) -> j1.merge(j2))
                            .toString())
            .expectedResult(join(data, ","))
            .exercise();

    withData(data)
            .terminal(s -> s.map(Object::toString)
                            .collect(() -> new StringJoiner(",", "[", "]"),
                                     (sj, cs) -> sj.add(cs),
                                     (j1, j2) -> j1.merge(j2))
                            .toString())
            .expectedResult("[" + join(data, ",") + "]")
            .exercise();
}