/*
 * Copyright (c) 2013, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 * @test
 * @summary Spliterator traversing and splitting tests
 * @library ../stream/bootlib
 * @build java.base/java.util.SpliteratorOfIntDataBuilder
 *        java.base/java.util.SpliteratorTestHelper
 * @run testng SpliteratorTraversingAndSplittingTest
 * @bug 8020016 8071477 8072784 8169838
 */

import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

import java.nio.CharBuffer;
import java.util.AbstractCollection;
import java.util.AbstractList;
import java.util.AbstractSet;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.RandomAccess;
import java.util.Set;
import java.util.SortedSet;
import java.util.Spliterator;
import java.util.SpliteratorOfIntDataBuilder;
import java.util.SpliteratorTestHelper;
import java.util.Spliterators;
import java.util.Stack;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.Vector;
import java.util.WeakHashMap;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ConcurrentSkipListMap;
import java.util.concurrent.ConcurrentSkipListSet;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.LinkedTransferQueue;
import java.util.concurrent.PriorityBlockingQueue;
import java.util.function.Consumer;
import java.util.function.DoubleConsumer;
import java.util.function.Function;
import java.util.function.IntConsumer;
import java.util.function.LongConsumer;
import java.util.function.Supplier;
import java.util.function.UnaryOperator;

public class SpliteratorTraversingAndSplittingTest extends SpliteratorTestHelper {

    private static final List<Integer> SIZES = Arrays.asList(0, 1, 10, 42);

    private static final String LOW = new String(new char[] {Character.MIN_LOW_SURROGATE});
    private static final String HIGH = new String(new char[] {Character.MIN_HIGH_SURROGATE});
    private static final String HIGH_LOW = HIGH + LOW;
    private static final String CHAR_HIGH_LOW = "A" + HIGH_LOW;
    private static final String HIGH_LOW_CHAR = HIGH_LOW + "A";
    private static final String CHAR_HIGH_LOW_CHAR = "A" + HIGH_LOW + "A";

    private static final List<String> STRINGS = generateTestStrings();

    private static List<String> generateTestStrings() {
        List<String> strings = new ArrayList<>();
        for (int n : Arrays.asList(1, 2, 3, 16, 17)) {
            strings.add(generate("A", n));
            strings.add(generate(LOW, n));
            strings.add(generate(HIGH, n));
            strings.add(generate(HIGH_LOW, n));
            strings.add(generate(CHAR_HIGH_LOW, n));
            strings.add(generate(HIGH_LOW_CHAR, n));
            strings.add(generate(CHAR_HIGH_LOW_CHAR, n));
        }
        return strings;
    }

    private static String generate(String s, int n) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < n; i++) {
            sb.append(s);
        }
        return sb.toString();
    }

    private static class SpliteratorDataBuilder<T> {
        List<Object[]> data;

        List<T> exp;

        Map<T, T> mExp;

        SpliteratorDataBuilder(List<Object[]> data, List<T> exp) {
            this.data = data;
            this.exp = exp;
            this.mExp = createMap(exp);
        }

        Map<T, T> createMap(List<T> l) {
            Map<T, T> m = new LinkedHashMap<>();
            for (T t : l) {
                m.put(t, t);
            }
            return m;
        }

        void add(String description, Collection<?> expected, Supplier<Spliterator<?>> s) {
            description = joiner(description).toString();
            data.add(new Object[]{description, expected, s});
        }

        void add(String description, Supplier<Spliterator<?>> s) {
            add(description, exp, s);
        }

        void addCollection(Function<Collection<T>, ? extends Collection<T>> c) {
            add("new " + c.apply(Collections.<T>emptyList()).getClass().getName() + ".spliterator()",
                () -> c.apply(exp).spliterator());
        }

        void addList(Function<Collection<T>, ? extends List<T>> l) {
            addCollection(l);
            addCollection(l.andThen(list -> list.subList(0, list.size())));
        }

        void addMap(Function<Map<T, T>, ? extends Map<T, T>> m) {
            String description = "new " + m.apply(Collections.<T, T>emptyMap()).getClass().getName();
            addMap(m, description);
        }

        void addMap(Function<Map<T, T>, ? extends Map<T, T>> m, String description) {
            add(description + ".keySet().spliterator()", () -> m.apply(mExp).keySet().spliterator());
            add(description + ".values().spliterator()", () -> m.apply(mExp).values().spliterator());
            add(description + ".entrySet().spliterator()", mExp.entrySet(), () -> m.apply(mExp).entrySet().spliterator());
        }

        StringBuilder joiner(String description) {
            return new StringBuilder(description).
                    append(" {").
                    append("size=").append(exp.size()).
                    append("}");
        }
    }

    static Object[][] spliteratorDataProvider;

    @DataProvider(name = "Spliterator<Integer>")
    public static Object[][] spliteratorDataProvider() {
        if (spliteratorDataProvider != null) {
            return spliteratorDataProvider;
        }

        List<Object[]> data = new ArrayList<>();
        for (int size : SIZES) {
            List<Integer> exp = listIntRange(size);
            SpliteratorDataBuilder<Integer> db = new SpliteratorDataBuilder<>(data, exp);

            // Direct spliterator methods

            db.add("Spliterators.spliterator(Collection, ...)",
                   () -> Spliterators.spliterator(exp, 0));

            db.add("Spliterators.spliterator(Iterator, ...)",
                   () -> Spliterators.spliterator(exp.iterator(), exp.size(), 0));

            db.add("Spliterators.spliteratorUnknownSize(Iterator, ...)",
                   () -> Spliterators.spliteratorUnknownSize(exp.iterator(), 0));

            db.add("Spliterators.spliterator(Spliterators.iteratorFromSpliterator(Spliterator ), ...)",
                   () -> Spliterators.spliterator(Spliterators.iterator(exp.spliterator()), exp.size(), 0));

            db.add("Spliterators.spliterator(T[], ...)",
                   () -> Spliterators.spliterator(exp.toArray(new Integer[0]), 0));

            db.add("Arrays.spliterator(T[], ...)",
                   () -> Arrays.spliterator(exp.toArray(new Integer[0])));

            class SpliteratorFromIterator extends Spliterators.AbstractSpliterator<Integer> {
                Iterator<Integer> it;

                SpliteratorFromIterator(Iterator<Integer> it, long est) {
                    super(est, Spliterator.SIZED);
                    this.it = it;
                }

                @Override
                public boolean tryAdvance(Consumer<? super Integer> action) {
                    if (action == null)
                        throw new NullPointerException();
                    if (it.hasNext()) {
                        action.accept(it.next());
                        return true;
                    }
                    else {
                        return false;
                    }
                }
            }
            db.add("new Spliterators.AbstractSpliterator()",
                   () -> new SpliteratorFromIterator(exp.iterator(), exp.size()));

            // Collections

            // default method implementations

            class AbstractCollectionImpl extends AbstractCollection<Integer> {
                Collection<Integer> c;

                AbstractCollectionImpl(Collection<Integer> c) {
                    this.c = c;
                }

                @Override
                public Iterator<Integer> iterator() {
                    return c.iterator();
                }

                @Override
                public int size() {
                    return c.size();
                }
            }
            db.addCollection(
                    c -> new AbstractCollectionImpl(c));

            class AbstractListImpl extends AbstractList<Integer> {
                List<Integer> l;

                AbstractListImpl(Collection<Integer> c) {
                    this.l = new ArrayList<>(c);
                }

                @Override
                public Integer get(int index) {
                    return l.get(index);
                }

                @Override
                public int size() {
                    return l.size();
                }
            }
            db.addCollection(
                    c -> new AbstractListImpl(c));

            class AbstractSetImpl extends AbstractSet<Integer> {
                Set<Integer> s;

                AbstractSetImpl(Collection<Integer> c) {
                    this.s = new HashSet<>(c);
                }

                @Override
                public Iterator<Integer> iterator() {
                    return s.iterator();
                }

                @Override
                public int size() {
                    return s.size();
                }
            }
            db.addCollection(
                    c -> new AbstractSetImpl(c));

            class AbstractSortedSetImpl extends AbstractSet<Integer> implements SortedSet<Integer> {
                SortedSet<Integer> s;

                AbstractSortedSetImpl(Collection<Integer> c) {
                    this.s = new TreeSet<>(c);
                }

                @Override
                public Iterator<Integer> iterator() {
                    return s.iterator();
                }

                @Override
                public int size() {
                    return s.size();
                }

                @Override
                public Comparator<? super Integer> comparator() {
                    return s.comparator();
                }

                @Override
                public SortedSet<Integer> subSet(Integer fromElement, Integer toElement) {
                    return s.subSet(fromElement, toElement);
                }

                @Override
                public SortedSet<Integer> headSet(Integer toElement) {
                    return s.headSet(toElement);
                }

                @Override
                public SortedSet<Integer> tailSet(Integer fromElement) {
                    return s.tailSet(fromElement);
                }

                @Override
                public Integer first() {
                    return s.first();
                }

                @Override
                public Integer last() {
                    return s.last();
                }

                @Override
                public Spliterator<Integer> spliterator() {
                    return SortedSet.super.spliterator();
                }
            }
            db.addCollection(
                    c -> new AbstractSortedSetImpl(c));

            class IterableWrapper implements Iterable<Integer> {
                final Iterable<Integer> it;

                IterableWrapper(Iterable<Integer> it) {
                    this.it = it;
                }

                @Override
                public Iterator<Integer> iterator() {
                    return it.iterator();
                }
            }
            db.add("new Iterable.spliterator()",
                   () -> new IterableWrapper(exp).spliterator());

            //

            db.add("Arrays.asList().spliterator()",
                   () -> Spliterators.spliterator(Arrays.asList(exp.toArray(new Integer[0])), 0));

            db.addList(ArrayList::new);

            db.addList(LinkedList::new);

            db.addList(Vector::new);

            class AbstractRandomAccessListImpl extends AbstractList<Integer> implements RandomAccess {
                Integer[] ia;

                AbstractRandomAccessListImpl(Collection<Integer> c) {
                    this.ia = c.toArray(new Integer[c.size()]);
                }

                @Override
                public Integer get(int index) {
                    return ia[index];
                }

                @Override
                public int size() {
                    return ia.length;
                }
            }
            db.addList(AbstractRandomAccessListImpl::new);

            class RandomAccessListImpl implements List<Integer>, RandomAccess {
                Integer[] ia;
                List<Integer> l;

                RandomAccessListImpl(Collection<Integer> c) {
                    this.ia = c.toArray(new Integer[c.size()]);
                    this.l = Arrays.asList(ia);
                }

                @Override
                public Integer get(int index) {
                    return ia[index];
                }

                @Override
                public Integer set(int index, Integer element) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public void add(int index, Integer element) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public Integer remove(int index) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public int indexOf(Object o) {
                    return l.indexOf(o);
                }

                @Override
                public int lastIndexOf(Object o) {
                    return Arrays.asList(ia).lastIndexOf(o);
                }

                @Override
                public ListIterator<Integer> listIterator() {
                    return l.listIterator();
                }

                @Override
                public ListIterator<Integer> listIterator(int index) {
                    return l.listIterator(index);
                }

                @Override
                public List<Integer> subList(int fromIndex, int toIndex) {
                    return l.subList(fromIndex, toIndex);
                }

                @Override
                public int size() {
                    return ia.length;
                }

                @Override
                public boolean isEmpty() {
                    return size() != 0;
                }

                @Override
                public boolean contains(Object o) {
                    return l.contains(o);
                }

                @Override
                public Iterator<Integer> iterator() {
                    return l.iterator();
                }

                @Override
                public Object[] toArray() {
                    return l.toArray();
                }

                @Override
                public <T> T[] toArray(T[] a) {
                    return l.toArray(a);
                }

                @Override
                public boolean add(Integer integer) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public boolean remove(Object o) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public boolean containsAll(Collection<?> c) {
                    return l.containsAll(c);
                }

                @Override
                public boolean addAll(Collection<? extends Integer> c) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public boolean addAll(int index, Collection<? extends Integer> c) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public boolean removeAll(Collection<?> c) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public boolean retainAll(Collection<?> c) {
                    throw new UnsupportedOperationException();
                }

                @Override
                public void clear() {
                    throw new UnsupportedOperationException();
                }
            }
            db.addList(RandomAccessListImpl::new);

            db.addCollection(HashSet::new);

            db.addCollection(LinkedHashSet::new);

            db.addCollection(TreeSet::new);


            db.addCollection(c -> { Stack<Integer> s = new Stack<>(); s.addAll(c); return s;});

            db.addCollection(PriorityQueue::new);

            db.addCollection(ArrayDeque::new);


            db.addCollection(ConcurrentSkipListSet::new);

            if (size > 0) {
                db.addCollection(c -> {
                    ArrayBlockingQueue<Integer> abq = new ArrayBlockingQueue<>(size);
                    abq.addAll(c);
                    return abq;
                });
            }

            db.addCollection(PriorityBlockingQueue::new);

            db.addCollection(LinkedBlockingQueue::new);

            db.addCollection(LinkedTransferQueue::new);

            db.addCollection(ConcurrentLinkedQueue::new);

            db.addCollection(LinkedBlockingDeque::new);

            db.addCollection(CopyOnWriteArrayList::new);

            db.addCollection(CopyOnWriteArraySet::new);

            if (size == 0) {
                db.addCollection(c -> Collections.<Integer>emptySet());
                db.addList(c -> Collections.<Integer>emptyList());
            }
            else if (size == 1) {
                db.addCollection(c -> Collections.singleton(exp.get(0)));
                db.addCollection(c -> Collections.singletonList(exp.get(0)));
            }

            {
                Integer[] ai = new Integer[size];
                Arrays.fill(ai, 1);
                db.add(String.format("Collections.nCopies(%d, 1)", exp.size()),
                       Arrays.asList(ai),
                       () -> Collections.nCopies(exp.size(), 1).spliterator());
            }

            // Collections.synchronized/unmodifiable/checked wrappers
            db.addCollection(Collections::unmodifiableCollection);
            db.addCollection(c -> Collections.unmodifiableSet(new HashSet<>(c)));
            db.addCollection(c -> Collections.unmodifiableSortedSet(new TreeSet<>(c)));
            db.addList(c -> Collections.unmodifiableList(new ArrayList<>(c)));
            db.addMap(Collections::unmodifiableMap);
            db.addMap(m -> Collections.unmodifiableSortedMap(new TreeMap<>(m)));

            db.addCollection(Collections::synchronizedCollection);
            db.addCollection(c -> Collections.synchronizedSet(new HashSet<>(c)));
            db.addCollection(c -> Collections.synchronizedSortedSet(new TreeSet<>(c)));
            db.addList(c -> Collections.synchronizedList(new ArrayList<>(c)));
            db.addMap(Collections::synchronizedMap);
            db.addMap(m -> Collections.synchronizedSortedMap(new TreeMap<>(m)));

            db.addCollection(c -> Collections.checkedCollection(c, Integer.class));
            db.addCollection(c -> Collections.checkedQueue(new ArrayDeque<>(c), Integer.class));
            db.addCollection(c -> Collections.checkedSet(new HashSet<>(c), Integer.class));
            db.addCollection(c -> Collections.checkedSortedSet(new TreeSet<>(c), Integer.class));
            db.addList(c -> Collections.checkedList(new ArrayList<>(c), Integer.class));
            db.addMap(c -> Collections.checkedMap(c, Integer.class, Integer.class));
            db.addMap(m -> Collections.checkedSortedMap(new TreeMap<>(m), Integer.class, Integer.class));

            // Maps

            db.addMap(HashMap::new);

            db.addMap(m -> {
                // Create a Map ensuring that for large sizes
                // buckets will contain 2 or more entries
                HashMap<Integer, Integer> cm = new HashMap<>(1, m.size() + 1);
                // Don't use putAll which inflates the table by
                // m.size() * loadFactor, thus creating a very sparse
                // map for 1000 entries defeating the purpose of this test,
                // in addition it will cause the split until null test to fail
                // because the number of valid splits is larger than the
                // threshold
                for (Map.Entry<Integer, Integer> e : m.entrySet())
                    cm.put(e.getKey(), e.getValue());
                return cm;
            }, "new java.util.HashMap(1, size + 1)");

            db.addMap(LinkedHashMap::new);

            db.addMap(IdentityHashMap::new);

            db.addMap(WeakHashMap::new);

            db.addMap(m -> {
                // Create a Map ensuring that for large sizes
                // buckets will be consist of 2 or more entries
                WeakHashMap<Integer, Integer> cm = new WeakHashMap<>(1, m.size() + 1);
                for (Map.Entry<Integer, Integer> e : m.entrySet())
                    cm.put(e.getKey(), e.getValue());
                return cm;
            }, "new java.util.WeakHashMap(1, size + 1)");

            // @@@  Descending maps etc
            db.addMap(TreeMap::new);

            db.addMap(ConcurrentHashMap::new);

            db.addMap(ConcurrentSkipListMap::new);

            if (size == 0) {
                db.addMap(m -> Collections.<Integer, Integer>emptyMap());
            }
            else if (size == 1) {
                db.addMap(m -> Collections.singletonMap(exp.get(0), exp.get(0)));
            }
        }

        return spliteratorDataProvider = data.toArray(new Object[0][]);
    }

    private static List<Integer> listIntRange(int upTo) {
        List<Integer> exp = new ArrayList<>();
        for (int i = 0; i < upTo; i++)
            exp.add(i);
        return Collections.unmodifiableList(exp);
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testNullPointerException(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        assertThrowsNPE(() -> s.get().forEachRemaining(null));
        assertThrowsNPE(() -> s.get().tryAdvance(null));
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testForEach(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testForEach(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testTryAdvance(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testTryAdvance(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testMixedTryAdvanceForEach(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testMixedTryAdvanceForEach(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testMixedTraverseAndSplit(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testMixedTraverseAndSplit(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testSplitAfterFullTraversal(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testSplitAfterFullTraversal(s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testSplitOnce(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testSplitOnce(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testSplitSixDeep(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testSplitSixDeep(exp, s, UnaryOperator.identity());
    }

    @Test(dataProvider = "Spliterator<Integer>")
    public void testSplitUntilNull(String description, Collection<Integer> exp, Supplier<Spliterator<Integer>> s) {
        testSplitUntilNull(exp, s, UnaryOperator.identity());
    }

    //
    private static class SpliteratorOfIntCharDataBuilder {
        List<Object[]> data;

        String s;

        List<Integer> expChars;

        List<Integer> expCodePoints;

        SpliteratorOfIntCharDataBuilder(List<Object[]> data, String s) {
            this.data = data;
            this.s = s;
            this.expChars = transform(s, false);
            this.expCodePoints = transform(s, true);
        }

        static List<Integer> transform(String s, boolean toCodePoints) {
            List<Integer> l = new ArrayList<>();

            if (!toCodePoints) {
                for (int i = 0; i < s.length(); i++) {
                    l.add((int) s.charAt(i));
                }
            }
            else {
                for (int i = 0; i < s.length();) {
                    char c1 = s.charAt(i++);
                    int cp = c1;
                    if (Character.isHighSurrogate(c1) && i < s.length()) {
                        char c2 = s.charAt(i);
                        if (Character.isLowSurrogate(c2)) {
                            i++;
                            cp = Character.toCodePoint(c1, c2);
                        }
                    }
                    l.add(cp);
                }
            }
            return l;
        }

        void add(String description, Function<String, CharSequence> f) {
            description = description.replace("%s", s);
            {
                Supplier<Spliterator.OfInt> supplier = () -> f.apply(s).chars().spliterator();
                data.add(new Object[]{description + ".chars().spliterator()", expChars, supplier});
            }
            {
                Supplier<Spliterator.OfInt> supplier = () -> f.apply(s).codePoints().spliterator();
                data.add(new Object[]{description + ".codePoints().spliterator()", expCodePoints, supplier});
            }
        }
    }

    static Object[][] spliteratorOfIntDataProvider;

    @DataProvider(name = "Spliterator.OfInt")
    public static Object[][] spliteratorOfIntDataProvider() {
        if (spliteratorOfIntDataProvider != null) {
            return spliteratorOfIntDataProvider;
        }

        List<Object[]> data = new ArrayList<>();
        for (int size : SIZES) {
            int exp[] = arrayIntRange(size);
            SpliteratorOfIntDataBuilder db = new SpliteratorOfIntDataBuilder(data, listIntRange(size));

            db.add("Spliterators.spliterator(int[], ...)",
                   () -> Spliterators.spliterator(exp, 0));

            db.add("Arrays.spliterator(int[], ...)",
                   () -> Arrays.spliterator(exp));

            db.add("Spliterators.spliterator(PrimitiveIterator.OfInt, ...)",
                   () -> Spliterators.spliterator(Spliterators.iterator(Arrays.spliterator(exp)), exp.length, 0));

            db.add("Spliterators.spliteratorUnknownSize(PrimitiveIterator.OfInt, ...)",
                   () -> Spliterators.spliteratorUnknownSize(Spliterators.iterator(Arrays.spliterator(exp)), 0));

            class IntSpliteratorFromArray extends Spliterators.AbstractIntSpliterator {
                int[] a;
                int index = 0;

                IntSpliteratorFromArray(int[] a) {
                    super(a.length, Spliterator.SIZED);
                    this.a = a;
                }

                @Override
                public boolean tryAdvance(IntConsumer action) {
                    if (action == null)
                        throw new NullPointerException();
                    if (index < a.length) {
                        action.accept(a[index++]);
                        return true;
                    }
                    else {
                        return false;
                    }
                }
            }
            db.add("new Spliterators.AbstractIntAdvancingSpliterator()",
                   () -> new IntSpliteratorFromArray(exp));
        }

        // Class for testing default methods
        class CharSequenceImpl implements CharSequence {
            final String s;

            public CharSequenceImpl(String s) {
                this.s = s;
            }

            @Override
            public int length() {
                return s.length();
            }

            @Override
            public char charAt(int index) {
                return s.charAt(index);
            }

            @Override
            public CharSequence subSequence(int start, int end) {
                return s.subSequence(start, end);
            }

            @Override
            public String toString() {
                return s;
            }
        }

        for (String string : STRINGS) {
            SpliteratorOfIntCharDataBuilder cdb = new SpliteratorOfIntCharDataBuilder(data, string);
            cdb.add("\"%s\"", s -> s);
            cdb.add("new CharSequenceImpl(\"%s\")", CharSequenceImpl::new);
            cdb.add("new StringBuilder(\"%s\")", StringBuilder::new);
            cdb.add("new StringBuffer(\"%s\")", StringBuffer::new);
            cdb.add("CharBuffer.wrap(\"%s\".toCharArray())", s -> CharBuffer.wrap(s.toCharArray()));
        }

        return spliteratorOfIntDataProvider = data.toArray(new Object[0][]);
    }

    private static int[] arrayIntRange(int upTo) {
        int[] exp = new int[upTo];
        for (int i = 0; i < upTo; i++)
            exp[i] = i;
        return exp;
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntNullPointerException(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        assertThrowsNPE(() -> s.get().forEachRemaining((IntConsumer) null));
        assertThrowsNPE(() -> s.get().tryAdvance((IntConsumer) null));
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntForEach(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testForEach(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntTryAdvance(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testTryAdvance(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntMixedTryAdvanceForEach(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testMixedTryAdvanceForEach(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntMixedTraverseAndSplit(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testMixedTraverseAndSplit(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntSplitAfterFullTraversal(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testSplitAfterFullTraversal(s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntSplitOnce(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testSplitOnce(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntSplitSixDeep(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testSplitSixDeep(exp, s, intBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfInt")
    public void testIntSplitUntilNull(String description, Collection<Integer> exp, Supplier<Spliterator.OfInt> s) {
        testSplitUntilNull(exp, s, intBoxingConsumer());
    }

    //

    private static class SpliteratorOfLongDataBuilder {
        List<Object[]> data;

        List<Long> exp;

        SpliteratorOfLongDataBuilder(List<Object[]> data, List<Long> exp) {
            this.data = data;
            this.exp = exp;
        }

        void add(String description, List<Long> expected, Supplier<Spliterator.OfLong> s) {
            description = joiner(description).toString();
            data.add(new Object[]{description, expected, s});
        }

        void add(String description, Supplier<Spliterator.OfLong> s) {
            add(description, exp, s);
        }

        StringBuilder joiner(String description) {
            return new StringBuilder(description).
                    append(" {").
                    append("size=").append(exp.size()).
                    append("}");
        }
    }

    static Object[][] spliteratorOfLongDataProvider;

    @DataProvider(name = "Spliterator.OfLong")
    public static Object[][] spliteratorOfLongDataProvider() {
        if (spliteratorOfLongDataProvider != null) {
            return spliteratorOfLongDataProvider;
        }

        List<Object[]> data = new ArrayList<>();
        for (int size : SIZES) {
            long exp[] = arrayLongRange(size);
            SpliteratorOfLongDataBuilder db = new SpliteratorOfLongDataBuilder(data, listLongRange(size));

            db.add("Spliterators.spliterator(long[], ...)",
                   () -> Spliterators.spliterator(exp, 0));

            db.add("Arrays.spliterator(long[], ...)",
                   () -> Arrays.spliterator(exp));

            db.add("Spliterators.spliterator(PrimitiveIterator.OfLong, ...)",
                   () -> Spliterators.spliterator(Spliterators.iterator(Arrays.spliterator(exp)), exp.length, 0));

            db.add("Spliterators.spliteratorUnknownSize(PrimitiveIterator.OfLong, ...)",
                   () -> Spliterators.spliteratorUnknownSize(Spliterators.iterator(Arrays.spliterator(exp)), 0));

            class LongSpliteratorFromArray extends Spliterators.AbstractLongSpliterator {
                long[] a;
                int index = 0;

                LongSpliteratorFromArray(long[] a) {
                    super(a.length, Spliterator.SIZED);
                    this.a = a;
                }

                @Override
                public boolean tryAdvance(LongConsumer action) {
                    if (action == null)
                        throw new NullPointerException();
                    if (index < a.length) {
                        action.accept(a[index++]);
                        return true;
                    }
                    else {
                        return false;
                    }
                }
            }
            db.add("new Spliterators.AbstractLongAdvancingSpliterator()",
                   () -> new LongSpliteratorFromArray(exp));
        }

        return spliteratorOfLongDataProvider = data.toArray(new Object[0][]);
    }

    private static List<Long> listLongRange(int upTo) {
        List<Long> exp = new ArrayList<>();
        for (long i = 0; i < upTo; i++)
            exp.add(i);
        return Collections.unmodifiableList(exp);
    }

    private static long[] arrayLongRange(int upTo) {
        long[] exp = new long[upTo];
        for (int i = 0; i < upTo; i++)
            exp[i] = i;
        return exp;
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongNullPointerException(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        assertThrowsNPE(() -> s.get().forEachRemaining((LongConsumer) null));
        assertThrowsNPE(() -> s.get().tryAdvance((LongConsumer) null));
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongForEach(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testForEach(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongTryAdvance(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testTryAdvance(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongMixedTryAdvanceForEach(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testMixedTryAdvanceForEach(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongMixedTraverseAndSplit(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testMixedTraverseAndSplit(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongSplitAfterFullTraversal(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testSplitAfterFullTraversal(s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongSplitOnce(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testSplitOnce(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongSplitSixDeep(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testSplitSixDeep(exp, s, longBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfLong")
    public void testLongSplitUntilNull(String description, Collection<Long> exp, Supplier<Spliterator.OfLong> s) {
        testSplitUntilNull(exp, s, longBoxingConsumer());
    }

    //

    private static class SpliteratorOfDoubleDataBuilder {
        List<Object[]> data;

        List<Double> exp;

        SpliteratorOfDoubleDataBuilder(List<Object[]> data, List<Double> exp) {
            this.data = data;
            this.exp = exp;
        }

        void add(String description, List<Double> expected, Supplier<Spliterator.OfDouble> s) {
            description = joiner(description).toString();
            data.add(new Object[]{description, expected, s});
        }

        void add(String description, Supplier<Spliterator.OfDouble> s) {
            add(description, exp, s);
        }

        StringBuilder joiner(String description) {
            return new StringBuilder(description).
                    append(" {").
                    append("size=").append(exp.size()).
                    append("}");
        }
    }

    static Object[][] spliteratorOfDoubleDataProvider;

    @DataProvider(name = "Spliterator.OfDouble")
    public static Object[][] spliteratorOfDoubleDataProvider() {
        if (spliteratorOfDoubleDataProvider != null) {
            return spliteratorOfDoubleDataProvider;
        }

        List<Object[]> data = new ArrayList<>();
        for (int size : SIZES) {
            double exp[] = arrayDoubleRange(size);
            SpliteratorOfDoubleDataBuilder db = new SpliteratorOfDoubleDataBuilder(data, listDoubleRange(size));

            db.add("Spliterators.spliterator(double[], ...)",
                   () -> Spliterators.spliterator(exp, 0));

            db.add("Arrays.spliterator(double[], ...)",
                   () -> Arrays.spliterator(exp));

            db.add("Spliterators.spliterator(PrimitiveIterator.OfDouble, ...)",
                   () -> Spliterators.spliterator(Spliterators.iterator(Arrays.spliterator(exp)), exp.length, 0));

            db.add("Spliterators.spliteratorUnknownSize(PrimitiveIterator.OfDouble, ...)",
                   () -> Spliterators.spliteratorUnknownSize(Spliterators.iterator(Arrays.spliterator(exp)), 0));

            class DoubleSpliteratorFromArray extends Spliterators.AbstractDoubleSpliterator {
                double[] a;
                int index = 0;

                DoubleSpliteratorFromArray(double[] a) {
                    super(a.length, Spliterator.SIZED);
                    this.a = a;
                }

                @Override
                public boolean tryAdvance(DoubleConsumer action) {
                    if (action == null)
                        throw new NullPointerException();
                    if (index < a.length) {
                        action.accept(a[index++]);
                        return true;
                    }
                    else {
                        return false;
                    }
                }
            }
            db.add("new Spliterators.AbstractDoubleAdvancingSpliterator()",
                   () -> new DoubleSpliteratorFromArray(exp));
        }

        return spliteratorOfDoubleDataProvider = data.toArray(new Object[0][]);
    }

    private static List<Double> listDoubleRange(int upTo) {
        List<Double> exp = new ArrayList<>();
        for (double i = 0; i < upTo; i++)
            exp.add(i);
        return Collections.unmodifiableList(exp);
    }

    private static double[] arrayDoubleRange(int upTo) {
        double[] exp = new double[upTo];
        for (int i = 0; i < upTo; i++)
            exp[i] = i;
        return exp;
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleNullPointerException(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        assertThrowsNPE(() -> s.get().forEachRemaining((DoubleConsumer) null));
        assertThrowsNPE(() -> s.get().tryAdvance((DoubleConsumer) null));
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleForEach(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testForEach(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleTryAdvance(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testTryAdvance(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleMixedTryAdvanceForEach(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testMixedTryAdvanceForEach(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleMixedTraverseAndSplit(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testMixedTraverseAndSplit(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleSplitAfterFullTraversal(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testSplitAfterFullTraversal(s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleSplitOnce(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testSplitOnce(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleSplitSixDeep(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testSplitSixDeep(exp, s, doubleBoxingConsumer());
    }

    @Test(dataProvider = "Spliterator.OfDouble")
    public void testDoubleSplitUntilNull(String description, Collection<Double> exp, Supplier<Spliterator.OfDouble> s) {
        testSplitUntilNull(exp, s, doubleBoxingConsumer());
    }

}