diff -r a6dc784b18a8 -r b5015f742ba6 jdk/test/java/util/stream/bootlib/java.base/java/util/stream/SpliteratorTestHelper.java --- a/jdk/test/java/util/stream/bootlib/java.base/java/util/stream/SpliteratorTestHelper.java Thu Feb 16 14:47:39 2017 -0800 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,715 +0,0 @@ -/* - * Copyright (c) 2012, 2013, 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. - */ -package java.util.stream; - -import org.testng.annotations.Test; - -import java.util.ArrayDeque; -import java.util.ArrayList; -import java.util.Collection; -import java.util.Collections; -import java.util.Deque; -import java.util.HashMap; -import java.util.List; -import java.util.Map; -import java.util.Spliterator; -import java.util.function.*; - -import static org.testng.Assert.*; -import static org.testng.Assert.assertEquals; -import static org.testng.Assert.fail; - -/** - * Assertion methods for spliterators, to be called from other tests - */ -public class SpliteratorTestHelper { - - public interface ContentAsserter { - void assertContents(Collection actual, Collection expected, boolean isOrdered); - } - - private static ContentAsserter DEFAULT_CONTENT_ASSERTER - = SpliteratorTestHelper::assertContents; - - @SuppressWarnings("unchecked") - private static ContentAsserter defaultContentAsserter() { - return (ContentAsserter) DEFAULT_CONTENT_ASSERTER; - } - - public static void testSpliterator(Supplier> supplier) { - testSpliterator(supplier, defaultContentAsserter()); - } - - public static void testSpliterator(Supplier> supplier, - ContentAsserter asserter) { - testSpliterator(supplier, (Consumer b) -> b, asserter); - } - - public static void testIntSpliterator(Supplier supplier) { - testIntSpliterator(supplier, defaultContentAsserter()); - } - - public static void testIntSpliterator(Supplier supplier, - ContentAsserter asserter) { - class BoxingAdapter implements Consumer, IntConsumer { - private final Consumer b; - - BoxingAdapter(Consumer b) { - this.b = b; - } - - @Override - public void accept(Integer value) { - throw new IllegalStateException(); - } - - @Override - public void accept(int value) { - b.accept(value); - } - } - - testSpliterator(supplier, BoxingAdapter::new, asserter); - } - - public static void testLongSpliterator(Supplier supplier) { - testLongSpliterator(supplier, defaultContentAsserter()); - } - - public static void testLongSpliterator(Supplier supplier, - ContentAsserter asserter) { - class BoxingAdapter implements Consumer, LongConsumer { - private final Consumer b; - - BoxingAdapter(Consumer b) { - this.b = b; - } - - @Override - public void accept(Long value) { - throw new IllegalStateException(); - } - - @Override - public void accept(long value) { - b.accept(value); - } - } - - testSpliterator(supplier, BoxingAdapter::new, asserter); - } - - public static void testDoubleSpliterator(Supplier supplier) { - testDoubleSpliterator(supplier, defaultContentAsserter()); - } - - public static void testDoubleSpliterator(Supplier supplier, - ContentAsserter asserter) { - class BoxingAdapter implements Consumer, DoubleConsumer { - private final Consumer b; - - BoxingAdapter(Consumer b) { - this.b = b; - } - - @Override - public void accept(Double value) { - throw new IllegalStateException(); - } - - @Override - public void accept(double value) { - b.accept(value); - } - } - - testSpliterator(supplier, BoxingAdapter::new, asserter); - } - - static > void testSpliterator(Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - ArrayList fromForEach = new ArrayList<>(); - Spliterator spliterator = supplier.get(); - Consumer addToFromForEach = boxingAdapter.apply(fromForEach::add); - spliterator.forEachRemaining(addToFromForEach); - - Collection exp = Collections.unmodifiableList(fromForEach); - - testNullPointerException(supplier); - testForEach(exp, supplier, boxingAdapter, asserter); - testTryAdvance(exp, supplier, boxingAdapter, asserter); - testMixedTryAdvanceForEach(exp, supplier, boxingAdapter, asserter); - testMixedTraverseAndSplit(exp, supplier, boxingAdapter, asserter); - testSplitAfterFullTraversal(supplier, boxingAdapter); - testSplitOnce(exp, supplier, boxingAdapter, asserter); - testSplitSixDeep(exp, supplier, boxingAdapter, asserter); - testSplitUntilNull(exp, supplier, boxingAdapter, asserter); - } - - // - - private static > void testNullPointerException(Supplier s) { - S sp = s.get(); - // Have to check instances and use casts to avoid tripwire messages and - // directly test the primitive methods - if (sp instanceof Spliterator.OfInt) { - Spliterator.OfInt psp = (Spliterator.OfInt) sp; - executeAndCatch(NullPointerException.class, () -> psp.forEachRemaining((IntConsumer) null)); - executeAndCatch(NullPointerException.class, () -> psp.tryAdvance((IntConsumer) null)); - } - else if (sp instanceof Spliterator.OfLong) { - Spliterator.OfLong psp = (Spliterator.OfLong) sp; - executeAndCatch(NullPointerException.class, () -> psp.forEachRemaining((LongConsumer) null)); - executeAndCatch(NullPointerException.class, () -> psp.tryAdvance((LongConsumer) null)); - } - else if (sp instanceof Spliterator.OfDouble) { - Spliterator.OfDouble psp = (Spliterator.OfDouble) sp; - executeAndCatch(NullPointerException.class, () -> psp.forEachRemaining((DoubleConsumer) null)); - executeAndCatch(NullPointerException.class, () -> psp.tryAdvance((DoubleConsumer) null)); - } - else { - executeAndCatch(NullPointerException.class, () -> sp.forEachRemaining(null)); - executeAndCatch(NullPointerException.class, () -> sp.tryAdvance(null)); - } - } - - private static > void testForEach( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - ArrayList fromForEach = new ArrayList<>(); - spliterator = supplier.get(); - Consumer addToFromForEach = boxingAdapter.apply(fromForEach::add); - spliterator.forEachRemaining(addToFromForEach); - - // Assert that forEach now produces no elements - spliterator.forEachRemaining(boxingAdapter.apply( - e -> fail("Spliterator.forEach produced an element after spliterator exhausted: " + e))); - // Assert that tryAdvance now produce no elements - spliterator.tryAdvance(boxingAdapter.apply( - e -> fail("Spliterator.tryAdvance produced an element after spliterator exhausted: " + e))); - - // assert that size, tryAdvance, and forEach are consistent - if (sizeIfKnown >= 0) { - assertEquals(sizeIfKnown, exp.size()); - } - assertEquals(fromForEach.size(), exp.size()); - - asserter.assertContents(fromForEach, exp, isOrdered); - } - - private static > void testTryAdvance( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - spliterator = supplier.get(); - ArrayList fromTryAdvance = new ArrayList<>(); - Consumer addToFromTryAdvance = boxingAdapter.apply(fromTryAdvance::add); - while (spliterator.tryAdvance(addToFromTryAdvance)) { } - - // Assert that forEach now produces no elements - spliterator.forEachRemaining(boxingAdapter.apply( - e -> fail("Spliterator.forEach produced an element after spliterator exhausted: " + e))); - // Assert that tryAdvance now produce no elements - spliterator.tryAdvance(boxingAdapter.apply( - e -> fail("Spliterator.tryAdvance produced an element after spliterator exhausted: " + e))); - - // assert that size, tryAdvance, and forEach are consistent - if (sizeIfKnown >= 0) { - assertEquals(sizeIfKnown, exp.size()); - } - assertEquals(fromTryAdvance.size(), exp.size()); - - asserter.assertContents(fromTryAdvance, exp, isOrdered); - } - - private static > void testMixedTryAdvanceForEach( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - // tryAdvance first few elements, then forEach rest - ArrayList dest = new ArrayList<>(); - spliterator = supplier.get(); - Consumer addToDest = boxingAdapter.apply(dest::add); - for (int i = 0; i < 10 && spliterator.tryAdvance(addToDest); i++) { } - spliterator.forEachRemaining(addToDest); - - // Assert that forEach now produces no elements - spliterator.forEachRemaining(boxingAdapter.apply( - e -> fail("Spliterator.forEach produced an element after spliterator exhausted: " + e))); - // Assert that tryAdvance now produce no elements - spliterator.tryAdvance(boxingAdapter.apply( - e -> fail("Spliterator.tryAdvance produced an element after spliterator exhausted: " + e))); - - if (sizeIfKnown >= 0) { - assertEquals(sizeIfKnown, dest.size()); - } - assertEquals(dest.size(), exp.size()); - - asserter.assertContents(dest, exp, isOrdered); - } - - private static > void testMixedTraverseAndSplit( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - // tryAdvance first few elements, then forEach rest - ArrayList dest = new ArrayList<>(); - spliterator = supplier.get(); - Consumer b = boxingAdapter.apply(dest::add); - - Spliterator spl1, spl2, spl3; - spliterator.tryAdvance(b); - spl2 = spliterator.trySplit(); - if (spl2 != null) { - spl2.tryAdvance(b); - spl1 = spl2.trySplit(); - if (spl1 != null) { - spl1.tryAdvance(b); - spl1.forEachRemaining(b); - } - spl2.tryAdvance(b); - spl2.forEachRemaining(b); - } - spliterator.tryAdvance(b); - spl3 = spliterator.trySplit(); - if (spl3 != null) { - spl3.tryAdvance(b); - spl3.forEachRemaining(b); - } - spliterator.tryAdvance(b); - spliterator.forEachRemaining(b); - - if (sizeIfKnown >= 0) { - assertEquals(sizeIfKnown, dest.size()); - } - assertEquals(dest.size(), exp.size()); - - asserter.assertContents(dest, exp, isOrdered); - } - - private static > void testSplitAfterFullTraversal( - Supplier supplier, - UnaryOperator> boxingAdapter) { - // Full traversal using tryAdvance - Spliterator spliterator = supplier.get(); - while (spliterator.tryAdvance(boxingAdapter.apply(e -> { }))) { } - Spliterator split = spliterator.trySplit(); - assertNull(split); - - // Full traversal using forEach - spliterator = supplier.get(); - spliterator.forEachRemaining(boxingAdapter.apply(e -> { })); - split = spliterator.trySplit(); - assertNull(split); - - // Full traversal using tryAdvance then forEach - spliterator = supplier.get(); - spliterator.tryAdvance(boxingAdapter.apply(e -> { })); - spliterator.forEachRemaining(boxingAdapter.apply(e -> { })); - split = spliterator.trySplit(); - assertNull(split); - } - - private static > void testSplitOnce( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - ArrayList fromSplit = new ArrayList<>(); - Spliterator s1 = supplier.get(); - Spliterator s2 = s1.trySplit(); - long s1Size = s1.getExactSizeIfKnown(); - long s2Size = (s2 != null) ? s2.getExactSizeIfKnown() : 0; - Consumer addToFromSplit = boxingAdapter.apply(fromSplit::add); - if (s2 != null) - s2.forEachRemaining(addToFromSplit); - s1.forEachRemaining(addToFromSplit); - - if (sizeIfKnown >= 0) { - assertEquals(sizeIfKnown, fromSplit.size()); - if (s1Size >= 0 && s2Size >= 0) - assertEquals(sizeIfKnown, s1Size + s2Size); - } - - asserter.assertContents(fromSplit, exp, isOrdered); - } - - private static > void testSplitSixDeep( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - S spliterator = supplier.get(); - boolean isOrdered = spliterator.hasCharacteristics(Spliterator.ORDERED); - - for (int depth=0; depth < 6; depth++) { - List dest = new ArrayList<>(); - spliterator = supplier.get(); - - assertSpliterator(spliterator); - - // verify splitting with forEach - splitSixDeepVisitor(depth, 0, dest, spliterator, boxingAdapter, spliterator.characteristics(), false); - asserter.assertContents(dest, exp, isOrdered); - - // verify splitting with tryAdvance - dest.clear(); - spliterator = supplier.get(); - splitSixDeepVisitor(depth, 0, dest, spliterator, boxingAdapter, spliterator.characteristics(), true); - asserter.assertContents(dest, exp, isOrdered); - } - } - - private static > - void splitSixDeepVisitor(int depth, int curLevel, - List dest, S spliterator, UnaryOperator> boxingAdapter, - int rootCharacteristics, boolean useTryAdvance) { - if (curLevel < depth) { - long beforeSize = spliterator.getExactSizeIfKnown(); - Spliterator split = spliterator.trySplit(); - if (split != null) { - assertSpliterator(split, rootCharacteristics); - assertSpliterator(spliterator, rootCharacteristics); - - if ((rootCharacteristics & Spliterator.SUBSIZED) != 0 && - (rootCharacteristics & Spliterator.SIZED) != 0) { - assertEquals(beforeSize, split.estimateSize() + spliterator.estimateSize()); - } - splitSixDeepVisitor(depth, curLevel + 1, dest, split, boxingAdapter, rootCharacteristics, useTryAdvance); - } - splitSixDeepVisitor(depth, curLevel + 1, dest, spliterator, boxingAdapter, rootCharacteristics, useTryAdvance); - } - else { - long sizeIfKnown = spliterator.getExactSizeIfKnown(); - if (useTryAdvance) { - Consumer addToDest = boxingAdapter.apply(dest::add); - int count = 0; - while (spliterator.tryAdvance(addToDest)) { - ++count; - } - - if (sizeIfKnown >= 0) - assertEquals(sizeIfKnown, count); - - // Assert that forEach now produces no elements - spliterator.forEachRemaining(boxingAdapter.apply( - e -> fail("Spliterator.forEach produced an element after spliterator exhausted: " + e))); - - Spliterator split = spliterator.trySplit(); - assertNull(split); - } - else { - List leafDest = new ArrayList<>(); - Consumer addToLeafDest = boxingAdapter.apply(leafDest::add); - spliterator.forEachRemaining(addToLeafDest); - - if (sizeIfKnown >= 0) - assertEquals(sizeIfKnown, leafDest.size()); - - // Assert that forEach now produces no elements - spliterator.tryAdvance(boxingAdapter.apply( - e -> fail("Spliterator.tryAdvance produced an element after spliterator exhausted: " + e))); - - Spliterator split = spliterator.trySplit(); - assertNull(split); - - dest.addAll(leafDest); - } - } - } - - private static > void testSplitUntilNull( - Collection exp, - Supplier supplier, - UnaryOperator> boxingAdapter, - ContentAsserter asserter) { - Spliterator s = supplier.get(); - boolean isOrdered = s.hasCharacteristics(Spliterator.ORDERED); - assertSpliterator(s); - - List splits = new ArrayList<>(); - Consumer c = boxingAdapter.apply(splits::add); - - testSplitUntilNull(new SplitNode(c, s)); - asserter.assertContents(splits, exp, isOrdered); - } - - private static class SplitNode { - // Constant for every node - final Consumer c; - final int rootCharacteristics; - - final Spliterator s; - - SplitNode(Consumer c, Spliterator s) { - this(c, s.characteristics(), s); - } - - private SplitNode(Consumer c, int rootCharacteristics, Spliterator s) { - this.c = c; - this.rootCharacteristics = rootCharacteristics; - this.s = s; - } - - SplitNode fromSplit(Spliterator split) { - return new SplitNode<>(c, rootCharacteristics, split); - } - } - - /** - * Set the maximum stack capacity to 0.25MB. This should be more than enough to detect a bad spliterator - * while not unduly disrupting test infrastructure given the test data sizes that are used are small. - * Note that j.u.c.ForkJoinPool sets the max queue size to 64M (1 << 26). - */ - private static final int MAXIMUM_STACK_CAPACITY = 1 << 18; // 0.25MB - - private static void testSplitUntilNull(SplitNode e) { - // Use an explicit stack to avoid a StackOverflowException when testing a Spliterator - // that when repeatedly split produces a right-balanced (and maybe degenerate) tree, or - // for a spliterator that is badly behaved. - Deque> stack = new ArrayDeque<>(); - stack.push(e); - - int iteration = 0; - while (!stack.isEmpty()) { - assertTrue(iteration++ < MAXIMUM_STACK_CAPACITY, "Exceeded maximum stack modification count of 1 << 18"); - - e = stack.pop(); - Spliterator parentAndRightSplit = e.s; - - long parentEstimateSize = parentAndRightSplit.estimateSize(); - assertTrue(parentEstimateSize >= 0, - String.format("Split size estimate %d < 0", parentEstimateSize)); - - long parentSize = parentAndRightSplit.getExactSizeIfKnown(); - Spliterator leftSplit = parentAndRightSplit.trySplit(); - if (leftSplit == null) { - parentAndRightSplit.forEachRemaining(e.c); - continue; - } - - assertSpliterator(leftSplit, e.rootCharacteristics); - assertSpliterator(parentAndRightSplit, e.rootCharacteristics); - - if (parentEstimateSize != Long.MAX_VALUE && leftSplit.estimateSize() > 0 - && parentAndRightSplit.estimateSize() > 0) { - assertTrue(leftSplit.estimateSize() < parentEstimateSize, - String.format("Left split size estimate %d >= parent split size estimate %d", - leftSplit.estimateSize(), parentEstimateSize)); - assertTrue(parentAndRightSplit.estimateSize() < parentEstimateSize, - String.format("Right split size estimate %d >= parent split size estimate %d", - leftSplit.estimateSize(), parentEstimateSize)); - } - else { - assertTrue(leftSplit.estimateSize() <= parentEstimateSize, - String.format("Left split size estimate %d > parent split size estimate %d", - leftSplit.estimateSize(), parentEstimateSize)); - assertTrue(parentAndRightSplit.estimateSize() <= parentEstimateSize, - String.format("Right split size estimate %d > parent split size estimate %d", - leftSplit.estimateSize(), parentEstimateSize)); - } - - long leftSize = leftSplit.getExactSizeIfKnown(); - long rightSize = parentAndRightSplit.getExactSizeIfKnown(); - if (parentSize >= 0 && leftSize >= 0 && rightSize >= 0) - assertEquals(parentSize, leftSize + rightSize, - String.format("exact left split size %d + exact right split size %d != parent exact split size %d", - leftSize, rightSize, parentSize)); - - // Add right side to stack first so left side is popped off first - stack.push(e.fromSplit(parentAndRightSplit)); - stack.push(e.fromSplit(leftSplit)); - } - } - - private static void assertSpliterator(Spliterator s, int rootCharacteristics) { - if ((rootCharacteristics & Spliterator.SUBSIZED) != 0) { - assertTrue(s.hasCharacteristics(Spliterator.SUBSIZED), - "Child split is not SUBSIZED when root split is SUBSIZED"); - } - assertSpliterator(s); - } - - private static void assertSpliterator(Spliterator s) { - if (s.hasCharacteristics(Spliterator.SUBSIZED)) { - assertTrue(s.hasCharacteristics(Spliterator.SIZED)); - } - if (s.hasCharacteristics(Spliterator.SIZED)) { - assertTrue(s.estimateSize() != Long.MAX_VALUE); - assertTrue(s.getExactSizeIfKnown() >= 0); - } - try { - s.getComparator(); - assertTrue(s.hasCharacteristics(Spliterator.SORTED)); - } catch (IllegalStateException e) { - assertFalse(s.hasCharacteristics(Spliterator.SORTED)); - } - } - - private static void assertContents(Collection actual, Collection expected, boolean isOrdered) { - if (isOrdered) { - assertEquals(actual, expected); - } - else { - LambdaTestHelpers.assertContentsUnordered(actual, expected); - } - } - - private static void executeAndCatch(Class expected, Runnable r) { - Exception caught = null; - try { - r.run(); - } - catch (Exception e) { - caught = e; - } - - assertNotNull(caught, - String.format("No Exception was thrown, expected an Exception of %s to be thrown", - expected.getName())); - assertTrue(expected.isInstance(caught), - String.format("Exception thrown %s not an instance of %s", - caught.getClass().getName(), expected.getName())); - } - - static void mixedTraverseAndSplit(Consumer b, Spliterator splTop) { - Spliterator spl1, spl2, spl3; - splTop.tryAdvance(b); - spl2 = splTop.trySplit(); - if (spl2 != null) { - spl2.tryAdvance(b); - spl1 = spl2.trySplit(); - if (spl1 != null) { - spl1.tryAdvance(b); - spl1.forEachRemaining(b); - } - spl2.tryAdvance(b); - spl2.forEachRemaining(b); - } - splTop.tryAdvance(b); - spl3 = splTop.trySplit(); - if (spl3 != null) { - spl3.tryAdvance(b); - spl3.forEachRemaining(b); - } - splTop.tryAdvance(b); - splTop.forEachRemaining(b); - } - - static void mixedTraverseAndSplit(IntConsumer b, Spliterator.OfInt splTop) { - Spliterator.OfInt spl1, spl2, spl3; - splTop.tryAdvance(b); - spl2 = splTop.trySplit(); - if (spl2 != null) { - spl2.tryAdvance(b); - spl1 = spl2.trySplit(); - if (spl1 != null) { - spl1.tryAdvance(b); - spl1.forEachRemaining(b); - } - spl2.tryAdvance(b); - spl2.forEachRemaining(b); - } - splTop.tryAdvance(b); - spl3 = splTop.trySplit(); - if (spl3 != null) { - spl3.tryAdvance(b); - spl3.forEachRemaining(b); - } - splTop.tryAdvance(b); - splTop.forEachRemaining(b); - } - static void mixedTraverseAndSplit(LongConsumer b, Spliterator.OfLong splTop) { - Spliterator.OfLong spl1, spl2, spl3; - splTop.tryAdvance(b); - spl2 = splTop.trySplit(); - if (spl2 != null) { - spl2.tryAdvance(b); - spl1 = spl2.trySplit(); - if (spl1 != null) { - spl1.tryAdvance(b); - spl1.forEachRemaining(b); - } - spl2.tryAdvance(b); - spl2.forEachRemaining(b); - } - splTop.tryAdvance(b); - spl3 = splTop.trySplit(); - if (spl3 != null) { - spl3.tryAdvance(b); - spl3.forEachRemaining(b); - } - splTop.tryAdvance(b); - splTop.forEachRemaining(b); - } - - static void mixedTraverseAndSplit(DoubleConsumer b, Spliterator.OfDouble splTop) { - Spliterator.OfDouble spl1, spl2, spl3; - splTop.tryAdvance(b); - spl2 = splTop.trySplit(); - if (spl2 != null) { - spl2.tryAdvance(b); - spl1 = spl2.trySplit(); - if (spl1 != null) { - spl1.tryAdvance(b); - spl1.forEachRemaining(b); - } - spl2.tryAdvance(b); - spl2.forEachRemaining(b); - } - splTop.tryAdvance(b); - spl3 = splTop.trySplit(); - if (spl3 != null) { - spl3.tryAdvance(b); - spl3.forEachRemaining(b); - } - splTop.tryAdvance(b); - splTop.forEachRemaining(b); - } -}