/* * 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. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file: * * Written by Doug Lea with assistance from members of JCP JSR-166 * Expert Group and released to the public domain, as explained at * http://creativecommons.org/publicdomain/zero/1.0/ */ import java.util.Arrays; import java.util.BitSet; import java.util.Collection; import java.util.Comparator; import java.util.Iterator; import java.util.NavigableSet; import java.util.NoSuchElementException; import java.util.Random; import java.util.Set; import java.util.SortedSet; import java.util.concurrent.ConcurrentSkipListSet; import junit.framework.Test; import junit.framework.TestSuite; public class ConcurrentSkipListSetTest extends JSR166TestCase { public static void main(String[] args) { main(suite(), args); } public static Test suite() { return new TestSuite(ConcurrentSkipListSetTest.class); } static class MyReverseComparator implements Comparator { public int compare(Object x, Object y) { return ((Comparable)y).compareTo(x); } } /** * Returns a new set of given size containing consecutive * Integers 0 ... n - 1. */ private ConcurrentSkipListSet<Integer> populatedSet(int n) { ConcurrentSkipListSet<Integer> q = new ConcurrentSkipListSet<Integer>(); assertTrue(q.isEmpty()); for (int i = n - 1; i >= 0; i -= 2) assertTrue(q.add(new Integer(i))); for (int i = (n & 1); i < n; i += 2) assertTrue(q.add(new Integer(i))); assertFalse(q.isEmpty()); assertEquals(n, q.size()); return q; } /** * Returns a new set of first 5 ints. */ private ConcurrentSkipListSet set5() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); assertTrue(q.isEmpty()); q.add(one); q.add(two); q.add(three); q.add(four); q.add(five); assertEquals(5, q.size()); return q; } /** * A new set has unbounded capacity */ public void testConstructor1() { assertEquals(0, new ConcurrentSkipListSet().size()); } /** * Initializing from null Collection throws NPE */ public void testConstructor3() { try { new ConcurrentSkipListSet((Collection)null); shouldThrow(); } catch (NullPointerException success) {} } /** * Initializing from Collection of null elements throws NPE */ public void testConstructor4() { try { new ConcurrentSkipListSet(Arrays.asList(new Integer[SIZE])); shouldThrow(); } catch (NullPointerException success) {} } /** * Initializing from Collection with some null elements throws NPE */ public void testConstructor5() { Integer[] ints = new Integer[SIZE]; for (int i = 0; i < SIZE - 1; ++i) ints[i] = new Integer(i); try { new ConcurrentSkipListSet(Arrays.asList(ints)); shouldThrow(); } catch (NullPointerException success) {} } /** * Set contains all elements of collection used to initialize */ public void testConstructor6() { Integer[] ints = new Integer[SIZE]; for (int i = 0; i < SIZE; ++i) ints[i] = new Integer(i); ConcurrentSkipListSet q = new ConcurrentSkipListSet(Arrays.asList(ints)); for (int i = 0; i < SIZE; ++i) assertEquals(ints[i], q.pollFirst()); } /** * The comparator used in constructor is used */ public void testConstructor7() { MyReverseComparator cmp = new MyReverseComparator(); ConcurrentSkipListSet q = new ConcurrentSkipListSet(cmp); assertEquals(cmp, q.comparator()); Integer[] ints = new Integer[SIZE]; for (int i = 0; i < SIZE; ++i) ints[i] = new Integer(i); q.addAll(Arrays.asList(ints)); for (int i = SIZE - 1; i >= 0; --i) assertEquals(ints[i], q.pollFirst()); } /** * isEmpty is true before add, false after */ public void testEmpty() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); assertTrue(q.isEmpty()); q.add(new Integer(1)); assertFalse(q.isEmpty()); q.add(new Integer(2)); q.pollFirst(); q.pollFirst(); assertTrue(q.isEmpty()); } /** * size changes when elements added and removed */ public void testSize() { ConcurrentSkipListSet q = populatedSet(SIZE); for (int i = 0; i < SIZE; ++i) { assertEquals(SIZE - i, q.size()); q.pollFirst(); } for (int i = 0; i < SIZE; ++i) { assertEquals(i, q.size()); q.add(new Integer(i)); } } /** * add(null) throws NPE */ public void testAddNull() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); try { q.add(null); shouldThrow(); } catch (NullPointerException success) {} } /** * Add of comparable element succeeds */ public void testAdd() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); assertTrue(q.add(zero)); assertTrue(q.add(one)); } /** * Add of duplicate element fails */ public void testAddDup() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); assertTrue(q.add(zero)); assertFalse(q.add(zero)); } /** * Add of non-Comparable throws CCE */ public void testAddNonComparable() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); try { q.add(new Object()); q.add(new Object()); shouldThrow(); } catch (ClassCastException success) { assertTrue(q.size() < 2); for (int i = 0, size = q.size(); i < size; i++) assertTrue(q.pollFirst().getClass() == Object.class); assertNull(q.pollFirst()); assertTrue(q.isEmpty()); assertEquals(0, q.size()); } } /** * addAll(null) throws NPE */ public void testAddAll1() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); try { q.addAll(null); shouldThrow(); } catch (NullPointerException success) {} } /** * addAll of a collection with null elements throws NPE */ public void testAddAll2() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); Integer[] ints = new Integer[SIZE]; try { q.addAll(Arrays.asList(ints)); shouldThrow(); } catch (NullPointerException success) {} } /** * addAll of a collection with any null elements throws NPE after * possibly adding some elements */ public void testAddAll3() { ConcurrentSkipListSet q = new ConcurrentSkipListSet(); Integer[] ints = new Integer[SIZE]; for (int i = 0; i < SIZE - 1; ++i) ints[i] = new Integer(i); try { q.addAll(Arrays.asList(ints)); shouldThrow(); } catch (NullPointerException success) {} } /** * Set contains all elements of successful addAll */ public void testAddAll5() { Integer[] empty = new Integer[0]; Integer[] ints = new Integer[SIZE]; for (int i = 0; i < SIZE; ++i) ints[i] = new Integer(SIZE - 1 - i); ConcurrentSkipListSet q = new ConcurrentSkipListSet(); assertFalse(q.addAll(Arrays.asList(empty))); assertTrue(q.addAll(Arrays.asList(ints))); for (int i = 0; i < SIZE; ++i) assertEquals(i, q.pollFirst()); } /** * pollFirst succeeds unless empty */ public void testPollFirst() { ConcurrentSkipListSet q = populatedSet(SIZE); for (int i = 0; i < SIZE; ++i) { assertEquals(i, q.pollFirst()); } assertNull(q.pollFirst()); } /** * pollLast succeeds unless empty */ public void testPollLast() { ConcurrentSkipListSet q = populatedSet(SIZE); for (int i = SIZE - 1; i >= 0; --i) { assertEquals(i, q.pollLast()); } assertNull(q.pollFirst()); } /** * remove(x) removes x and returns true if present */ public void testRemoveElement() { ConcurrentSkipListSet q = populatedSet(SIZE); for (int i = 1; i < SIZE; i += 2) { assertTrue(q.contains(i)); assertTrue(q.remove(i)); assertFalse(q.contains(i)); assertTrue(q.contains(i - 1)); } for (int i = 0; i < SIZE; i += 2) { assertTrue(q.contains(i)); assertTrue(q.remove(i)); assertFalse(q.contains(i)); assertFalse(q.remove(i + 1)); assertFalse(q.contains(i + 1)); } assertTrue(q.isEmpty()); } /** * contains(x) reports true when elements added but not yet removed */ public void testContains() { ConcurrentSkipListSet q = populatedSet(SIZE); for (int i = 0; i < SIZE; ++i) { assertTrue(q.contains(new Integer(i))); q.pollFirst(); assertFalse(q.contains(new Integer(i))); } } /** * clear removes all elements */ public void testClear() { ConcurrentSkipListSet q = populatedSet(SIZE); q.clear(); assertTrue(q.isEmpty()); assertEquals(0, q.size()); q.add(new Integer(1)); assertFalse(q.isEmpty()); q.clear(); assertTrue(q.isEmpty()); } /** * containsAll(c) is true when c contains a subset of elements */ public void testContainsAll() { ConcurrentSkipListSet q = populatedSet(SIZE); ConcurrentSkipListSet p = new ConcurrentSkipListSet(); for (int i = 0; i < SIZE; ++i) { assertTrue(q.containsAll(p)); assertFalse(p.containsAll(q)); p.add(new Integer(i)); } assertTrue(p.containsAll(q)); } /** * retainAll(c) retains only those elements of c and reports true if changed */ public void testRetainAll() { ConcurrentSkipListSet q = populatedSet(SIZE); ConcurrentSkipListSet p = populatedSet(SIZE); for (int i = 0; i < SIZE; ++i) { boolean changed = q.retainAll(p); if (i == 0) assertFalse(changed); else assertTrue(changed); assertTrue(q.containsAll(p)); assertEquals(SIZE - i, q.size()); p.pollFirst(); } } /** * removeAll(c) removes only those elements of c and reports true if changed */ public void testRemoveAll() { for (int i = 1; i < SIZE; ++i) { ConcurrentSkipListSet q = populatedSet(SIZE); ConcurrentSkipListSet p = populatedSet(i); assertTrue(q.removeAll(p)); assertEquals(SIZE - i, q.size()); for (int j = 0; j < i; ++j) { Integer x = (Integer)(p.pollFirst()); assertFalse(q.contains(x)); } } } /** * lower returns preceding element */ public void testLower() { ConcurrentSkipListSet q = set5(); Object e1 = q.lower(three); assertEquals(two, e1); Object e2 = q.lower(six); assertEquals(five, e2); Object e3 = q.lower(one); assertNull(e3); Object e4 = q.lower(zero); assertNull(e4); } /** * higher returns next element */ public void testHigher() { ConcurrentSkipListSet q = set5(); Object e1 = q.higher(three); assertEquals(four, e1); Object e2 = q.higher(zero); assertEquals(one, e2); Object e3 = q.higher(five); assertNull(e3); Object e4 = q.higher(six); assertNull(e4); } /** * floor returns preceding element */ public void testFloor() { ConcurrentSkipListSet q = set5(); Object e1 = q.floor(three); assertEquals(three, e1); Object e2 = q.floor(six); assertEquals(five, e2); Object e3 = q.floor(one); assertEquals(one, e3); Object e4 = q.floor(zero); assertNull(e4); } /** * ceiling returns next element */ public void testCeiling() { ConcurrentSkipListSet q = set5(); Object e1 = q.ceiling(three); assertEquals(three, e1); Object e2 = q.ceiling(zero); assertEquals(one, e2); Object e3 = q.ceiling(five); assertEquals(five, e3); Object e4 = q.ceiling(six); assertNull(e4); } /** * toArray contains all elements in sorted order */ public void testToArray() { ConcurrentSkipListSet q = populatedSet(SIZE); Object[] o = q.toArray(); for (int i = 0; i < o.length; i++) assertSame(o[i], q.pollFirst()); } /** * toArray(a) contains all elements in sorted order */ public void testToArray2() { ConcurrentSkipListSet<Integer> q = populatedSet(SIZE); Integer[] ints = new Integer[SIZE]; assertSame(ints, q.toArray(ints)); for (int i = 0; i < ints.length; i++) assertSame(ints[i], q.pollFirst()); } /** * iterator iterates through all elements */ public void testIterator() { ConcurrentSkipListSet q = populatedSet(SIZE); Iterator it = q.iterator(); int i; for (i = 0; it.hasNext(); i++) assertTrue(q.contains(it.next())); assertEquals(i, SIZE); assertIteratorExhausted(it); } /** * iterator of empty set has no elements */ public void testEmptyIterator() { NavigableSet s = new ConcurrentSkipListSet(); assertIteratorExhausted(s.iterator()); assertIteratorExhausted(s.descendingSet().iterator()); } /** * iterator.remove removes current element */ public void testIteratorRemove() { final ConcurrentSkipListSet q = new ConcurrentSkipListSet(); q.add(new Integer(2)); q.add(new Integer(1)); q.add(new Integer(3)); Iterator it = q.iterator(); it.next(); it.remove(); it = q.iterator(); assertEquals(it.next(), new Integer(2)); assertEquals(it.next(), new Integer(3)); assertFalse(it.hasNext()); } /** * toString contains toStrings of elements */ public void testToString() { ConcurrentSkipListSet q = populatedSet(SIZE); String s = q.toString(); for (int i = 0; i < SIZE; ++i) { assertTrue(s.contains(String.valueOf(i))); } } /** * A deserialized serialized set has same elements */ public void testSerialization() throws Exception { NavigableSet x = populatedSet(SIZE); NavigableSet y = serialClone(x); assertNotSame(x, y); assertEquals(x.size(), y.size()); assertEquals(x, y); assertEquals(y, x); while (!x.isEmpty()) { assertFalse(y.isEmpty()); assertEquals(x.pollFirst(), y.pollFirst()); } assertTrue(y.isEmpty()); } /** * subSet returns set with keys in requested range */ public void testSubSetContents() { ConcurrentSkipListSet set = set5(); SortedSet sm = set.subSet(two, four); assertEquals(two, sm.first()); assertEquals(three, sm.last()); assertEquals(2, sm.size()); assertFalse(sm.contains(one)); assertTrue(sm.contains(two)); assertTrue(sm.contains(three)); assertFalse(sm.contains(four)); assertFalse(sm.contains(five)); Iterator i = sm.iterator(); Object k; k = (Integer)(i.next()); assertEquals(two, k); k = (Integer)(i.next()); assertEquals(three, k); assertFalse(i.hasNext()); Iterator j = sm.iterator(); j.next(); j.remove(); assertFalse(set.contains(two)); assertEquals(4, set.size()); assertEquals(1, sm.size()); assertEquals(three, sm.first()); assertEquals(three, sm.last()); assertTrue(sm.remove(three)); assertTrue(sm.isEmpty()); assertEquals(3, set.size()); } public void testSubSetContents2() { ConcurrentSkipListSet set = set5(); SortedSet sm = set.subSet(two, three); assertEquals(1, sm.size()); assertEquals(two, sm.first()); assertEquals(two, sm.last()); assertFalse(sm.contains(one)); assertTrue(sm.contains(two)); assertFalse(sm.contains(three)); assertFalse(sm.contains(four)); assertFalse(sm.contains(five)); Iterator i = sm.iterator(); Object k; k = (Integer)(i.next()); assertEquals(two, k); assertFalse(i.hasNext()); Iterator j = sm.iterator(); j.next(); j.remove(); assertFalse(set.contains(two)); assertEquals(4, set.size()); assertEquals(0, sm.size()); assertTrue(sm.isEmpty()); assertFalse(sm.remove(three)); assertEquals(4, set.size()); } /** * headSet returns set with keys in requested range */ public void testHeadSetContents() { ConcurrentSkipListSet set = set5(); SortedSet sm = set.headSet(four); assertTrue(sm.contains(one)); assertTrue(sm.contains(two)); assertTrue(sm.contains(three)); assertFalse(sm.contains(four)); assertFalse(sm.contains(five)); Iterator i = sm.iterator(); Object k; k = (Integer)(i.next()); assertEquals(one, k); k = (Integer)(i.next()); assertEquals(two, k); k = (Integer)(i.next()); assertEquals(three, k); assertFalse(i.hasNext()); sm.clear(); assertTrue(sm.isEmpty()); assertEquals(2, set.size()); assertEquals(four, set.first()); } /** * tailSet returns set with keys in requested range */ public void testTailSetContents() { ConcurrentSkipListSet set = set5(); SortedSet sm = set.tailSet(two); assertFalse(sm.contains(one)); assertTrue(sm.contains(two)); assertTrue(sm.contains(three)); assertTrue(sm.contains(four)); assertTrue(sm.contains(five)); Iterator i = sm.iterator(); Object k; k = (Integer)(i.next()); assertEquals(two, k); k = (Integer)(i.next()); assertEquals(three, k); k = (Integer)(i.next()); assertEquals(four, k); k = (Integer)(i.next()); assertEquals(five, k); assertFalse(i.hasNext()); SortedSet ssm = sm.tailSet(four); assertEquals(four, ssm.first()); assertEquals(five, ssm.last()); assertTrue(ssm.remove(four)); assertEquals(1, ssm.size()); assertEquals(3, sm.size()); assertEquals(4, set.size()); } Random rnd = new Random(666); /** * Subsets of subsets subdivide correctly */ public void testRecursiveSubSets() throws Exception { int setSize = expensiveTests ? 1000 : 100; Class cl = ConcurrentSkipListSet.class; NavigableSet<Integer> set = newSet(cl); BitSet bs = new BitSet(setSize); populate(set, setSize, bs); check(set, 0, setSize - 1, true, bs); check(set.descendingSet(), 0, setSize - 1, false, bs); mutateSet(set, 0, setSize - 1, bs); check(set, 0, setSize - 1, true, bs); check(set.descendingSet(), 0, setSize - 1, false, bs); bashSubSet(set.subSet(0, true, setSize, false), 0, setSize - 1, true, bs); } /** * addAll is idempotent */ public void testAddAll_idempotent() throws Exception { Set x = populatedSet(SIZE); Set y = new ConcurrentSkipListSet(x); y.addAll(x); assertEquals(x, y); assertEquals(y, x); } static NavigableSet<Integer> newSet(Class cl) throws Exception { NavigableSet<Integer> result = (NavigableSet<Integer>) cl.getConstructor().newInstance(); assertEquals(0, result.size()); assertFalse(result.iterator().hasNext()); return result; } void populate(NavigableSet<Integer> set, int limit, BitSet bs) { for (int i = 0, n = 2 * limit / 3; i < n; i++) { int element = rnd.nextInt(limit); put(set, element, bs); } } void mutateSet(NavigableSet<Integer> set, int min, int max, BitSet bs) { int size = set.size(); int rangeSize = max - min + 1; // Remove a bunch of entries directly for (int i = 0, n = rangeSize / 2; i < n; i++) { remove(set, min - 5 + rnd.nextInt(rangeSize + 10), bs); } // Remove a bunch of entries with iterator for (Iterator<Integer> it = set.iterator(); it.hasNext(); ) { if (rnd.nextBoolean()) { bs.clear(it.next()); it.remove(); } } // Add entries till we're back to original size while (set.size() < size) { int element = min + rnd.nextInt(rangeSize); assertTrue(element >= min && element <= max); put(set, element, bs); } } void mutateSubSet(NavigableSet<Integer> set, int min, int max, BitSet bs) { int size = set.size(); int rangeSize = max - min + 1; // Remove a bunch of entries directly for (int i = 0, n = rangeSize / 2; i < n; i++) { remove(set, min - 5 + rnd.nextInt(rangeSize + 10), bs); } // Remove a bunch of entries with iterator for (Iterator<Integer> it = set.iterator(); it.hasNext(); ) { if (rnd.nextBoolean()) { bs.clear(it.next()); it.remove(); } } // Add entries till we're back to original size while (set.size() < size) { int element = min - 5 + rnd.nextInt(rangeSize + 10); if (element >= min && element <= max) { put(set, element, bs); } else { try { set.add(element); shouldThrow(); } catch (IllegalArgumentException success) {} } } } void put(NavigableSet<Integer> set, int element, BitSet bs) { if (set.add(element)) bs.set(element); } void remove(NavigableSet<Integer> set, int element, BitSet bs) { if (set.remove(element)) bs.clear(element); } void bashSubSet(NavigableSet<Integer> set, int min, int max, boolean ascending, BitSet bs) { check(set, min, max, ascending, bs); check(set.descendingSet(), min, max, !ascending, bs); mutateSubSet(set, min, max, bs); check(set, min, max, ascending, bs); check(set.descendingSet(), min, max, !ascending, bs); // Recurse if (max - min < 2) return; int midPoint = (min + max) / 2; // headSet - pick direction and endpoint inclusion randomly boolean incl = rnd.nextBoolean(); NavigableSet<Integer> hm = set.headSet(midPoint, incl); if (ascending) { if (rnd.nextBoolean()) bashSubSet(hm, min, midPoint - (incl ? 0 : 1), true, bs); else bashSubSet(hm.descendingSet(), min, midPoint - (incl ? 0 : 1), false, bs); } else { if (rnd.nextBoolean()) bashSubSet(hm, midPoint + (incl ? 0 : 1), max, false, bs); else bashSubSet(hm.descendingSet(), midPoint + (incl ? 0 : 1), max, true, bs); } // tailSet - pick direction and endpoint inclusion randomly incl = rnd.nextBoolean(); NavigableSet<Integer> tm = set.tailSet(midPoint,incl); if (ascending) { if (rnd.nextBoolean()) bashSubSet(tm, midPoint + (incl ? 0 : 1), max, true, bs); else bashSubSet(tm.descendingSet(), midPoint + (incl ? 0 : 1), max, false, bs); } else { if (rnd.nextBoolean()) { bashSubSet(tm, min, midPoint - (incl ? 0 : 1), false, bs); } else { bashSubSet(tm.descendingSet(), min, midPoint - (incl ? 0 : 1), true, bs); } } // subSet - pick direction and endpoint inclusion randomly int rangeSize = max - min + 1; int[] endpoints = new int[2]; endpoints[0] = min + rnd.nextInt(rangeSize); endpoints[1] = min + rnd.nextInt(rangeSize); Arrays.sort(endpoints); boolean lowIncl = rnd.nextBoolean(); boolean highIncl = rnd.nextBoolean(); if (ascending) { NavigableSet<Integer> sm = set.subSet( endpoints[0], lowIncl, endpoints[1], highIncl); if (rnd.nextBoolean()) bashSubSet(sm, endpoints[0] + (lowIncl ? 0 : 1), endpoints[1] - (highIncl ? 0 : 1), true, bs); else bashSubSet(sm.descendingSet(), endpoints[0] + (lowIncl ? 0 : 1), endpoints[1] - (highIncl ? 0 : 1), false, bs); } else { NavigableSet<Integer> sm = set.subSet( endpoints[1], highIncl, endpoints[0], lowIncl); if (rnd.nextBoolean()) bashSubSet(sm, endpoints[0] + (lowIncl ? 0 : 1), endpoints[1] - (highIncl ? 0 : 1), false, bs); else bashSubSet(sm.descendingSet(), endpoints[0] + (lowIncl ? 0 : 1), endpoints[1] - (highIncl ? 0 : 1), true, bs); } } /** * min and max are both inclusive. If max < min, interval is empty. */ void check(NavigableSet<Integer> set, final int min, final int max, final boolean ascending, final BitSet bs) { class ReferenceSet { int lower(int element) { return ascending ? lowerAscending(element) : higherAscending(element); } int floor(int element) { return ascending ? floorAscending(element) : ceilingAscending(element); } int ceiling(int element) { return ascending ? ceilingAscending(element) : floorAscending(element); } int higher(int element) { return ascending ? higherAscending(element) : lowerAscending(element); } int first() { return ascending ? firstAscending() : lastAscending(); } int last() { return ascending ? lastAscending() : firstAscending(); } int lowerAscending(int element) { return floorAscending(element - 1); } int floorAscending(int element) { if (element < min) return -1; else if (element > max) element = max; // BitSet should support this! Test would run much faster while (element >= min) { if (bs.get(element)) return element; element--; } return -1; } int ceilingAscending(int element) { if (element < min) element = min; else if (element > max) return -1; int result = bs.nextSetBit(element); return result > max ? -1 : result; } int higherAscending(int element) { return ceilingAscending(element + 1); } private int firstAscending() { int result = ceilingAscending(min); return result > max ? -1 : result; } private int lastAscending() { int result = floorAscending(max); return result < min ? -1 : result; } } ReferenceSet rs = new ReferenceSet(); // Test contents using containsElement int size = 0; for (int i = min; i <= max; i++) { boolean bsContainsI = bs.get(i); assertEquals(bsContainsI, set.contains(i)); if (bsContainsI) size++; } assertEquals(size, set.size()); // Test contents using contains elementSet iterator int size2 = 0; int previousElement = -1; for (int element : set) { assertTrue(bs.get(element)); size2++; assertTrue(previousElement < 0 || (ascending ? element - previousElement > 0 : element - previousElement < 0)); previousElement = element; } assertEquals(size2, size); // Test navigation ops for (int element = min - 1; element <= max + 1; element++) { assertEq(set.lower(element), rs.lower(element)); assertEq(set.floor(element), rs.floor(element)); assertEq(set.higher(element), rs.higher(element)); assertEq(set.ceiling(element), rs.ceiling(element)); } // Test extrema if (set.size() != 0) { assertEq(set.first(), rs.first()); assertEq(set.last(), rs.last()); } else { assertEq(rs.first(), -1); assertEq(rs.last(), -1); try { set.first(); shouldThrow(); } catch (NoSuchElementException success) {} try { set.last(); shouldThrow(); } catch (NoSuchElementException success) {} } } static void assertEq(Integer i, int j) { if (i == null) assertEquals(j, -1); else assertEquals((int) i, j); } static boolean eq(Integer i, int j) { return (i == null) ? j == -1 : i == j; } }