util/Collections/EmptyNavigableSet.java

/*
 * Copyright (c) 2011, 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
 * @bug 4533691 7129185
 * @summary Unit test for Collections.emptyNavigableSet
 * @run testng EmptyNavigableSet
 */

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

import java.math.BigInteger;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedSet;
import java.util.TreeSet;

import static org.testng.Assert.assertFalse;
import static org.testng.Assert.assertSame;
import static org.testng.Assert.assertTrue;

public class EmptyNavigableSet {

    public static <T> void assertInstance(T actual, Class<? extends T> expected) {
        assertInstance(actual, expected, null);
    }

    public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {
        assertTrue(expected.isInstance(actual), ((null != message) ? message : "")
            + " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");
    }

    public static <T extends Throwable> void assertEmptyNavigableSet(Object obj) {
        assertInstance(obj, NavigableSet.class);
        assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0));
    }

    public static <T extends Throwable> void assertEmptyNavigableSet(Object obj, String message) {
        assertInstance(obj, NavigableSet.class, message);
        assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0),
            ((null != message) ? message : "") + " Not empty. ");
    }

    private <T extends Throwable> void assertThrows(Class<T> throwableClass,
                                                    ThrowingRunnable runnable,
                                                    String message) {
        try {
            Assert.assertThrows(throwableClass, runnable);
        } catch (AssertionError e) {
            throw new AssertionError(String.format("%s%n%s",
                    ((null != message) ? message : ""), e.getMessage()), e);
        }
    }

    private void assertThrowsCCE(ThrowingRunnable r, String s) {
        assertThrows(ClassCastException.class, r, s);
    }

    private void assertThrowsNPE(ThrowingRunnable r, String s) {
        assertThrows(NullPointerException.class, r, s);
    }

    private void assertThrowsIAE(ThrowingRunnable r, String s) {
        assertThrows(IllegalArgumentException.class, r, s);
    }

    private void assertThrowsNSEE(ThrowingRunnable r, String s) {
        assertThrows(NoSuchElementException.class, r, s);
    }

    public static final boolean isDescending(SortedSet<?> set) {
        if (null == set.comparator()) {
            // natural order
            return false;
        }

        if (Collections.reverseOrder() == set.comparator()) {
            // reverse natural order.
            return true;
        }

        if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {
            // it's a Collections.reverseOrder(Comparator).
            return true;
        }

        throw new IllegalStateException("can't determine ordering for " + set);
    }

    /**
     * Tests that the comparator is {@code null}.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testComparatorIsNull(String description, NavigableSet<?> navigableSet) {
        Comparator comparator = navigableSet.comparator();

        assertTrue(comparator == null || comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");
    }

    /**
     * Tests that contains requires Comparable
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testContainsRequiresComparable(String description, NavigableSet<?> navigableSet) {
        assertThrowsCCE(
            () -> navigableSet.contains(new Object()),
            description + ": Comparable should be required");
    }

    /**
     * Tests that the contains method returns {@code false}.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testContains(String description, NavigableSet<?> navigableSet) {
        assertFalse(navigableSet.contains(new Integer(1)),
            description + ": Should not contain any elements.");
    }

    /**
     * Tests that the containsAll method returns {@code false}.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testContainsAll(String description, NavigableSet<?> navigableSet) {
        TreeSet treeSet = new TreeSet();
        treeSet.add("1");
        treeSet.add("2");
        treeSet.add("3");

        assertFalse(navigableSet.containsAll(treeSet), "Should not contain any elements.");
    }

    /**
     * Tests that the iterator is empty.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testEmptyIterator(String description, NavigableSet<?> navigableSet) {
        Iterator emptyIterator = navigableSet.iterator();

        assertFalse((emptyIterator != null) && (emptyIterator.hasNext()),
            "The iterator is not empty.");
    }

    /**
     * Tests that the set is empty.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testIsEmpty(String description, NavigableSet<?> navigableSet) {
        assertTrue(navigableSet.isEmpty(), "The set is not empty.");
    }

    /**
     * Tests that the first() method throws NoSuchElementException
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testFirst(String description, NavigableSet<?> navigableSet) {
        assertThrowsNSEE(navigableSet::first, description);
    }

    /**
     * Tests the headSet() method.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testHeadSet(String description, NavigableSet navigableSet) {
        assertThrowsNPE(
            () -> { NavigableSet ns = navigableSet.headSet(null, false); },
            description + ": Must throw NullPointerException for null element");

        assertThrowsCCE(
            () -> { NavigableSet ns = navigableSet.headSet(new Object(), true); },
            description + ": Must throw ClassCastException for non-Comparable element");

        NavigableSet ns = navigableSet.headSet("1", false);

        assertEmptyNavigableSet(ns, description + ": Returned value is not empty navigable set.");
    }

    /**
     * Tests that the last() method throws NoSuchElementException
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testLast(String description, NavigableSet<?> navigableSet) {
        assertThrowsNSEE(navigableSet::last, description);
    }

    /**
     * Tests that the size is 0.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testSizeIsZero(String description, NavigableSet<?> navigableSet) {
        assertTrue(0 == navigableSet.size(), "The size of the set is not 0.");
    }

    /**
     * Tests the subSet() method.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testSubSet(String description, NavigableSet navigableSet) {
        assertThrowsNPE(
            () -> {
                SortedSet ss = navigableSet.subSet(null, BigInteger.TEN);
            },
            description + ": Must throw NullPointerException for null element");

        assertThrowsNPE(
            () -> {
                SortedSet ss = navigableSet.subSet(BigInteger.ZERO, null);
            },
            description + ": Must throw NullPointerException for null element");

        assertThrowsNPE(
            () -> {
                SortedSet ss = navigableSet.subSet(null, null);
            },
            description + ": Must throw NullPointerException for null element");

        Object obj1 = new Object();
        Object obj2 = new Object();

        assertThrowsCCE(
            () -> {
                SortedSet ss = navigableSet.subSet(obj1, BigInteger.TEN);
            },
            description + ": Must throw ClassCastException for parameter which is not Comparable.");

        assertThrowsCCE(
            () -> {
                SortedSet ss = navigableSet.subSet(BigInteger.ZERO, obj2);
            },
            description + ": Must throw ClassCastException for parameter which is not Comparable.");

        assertThrowsCCE(
            () -> {
                SortedSet ss = navigableSet.subSet(obj1, obj2);
            },
            description + ": Must throw ClassCastException for parameter which is not Comparable.");

        // minimal range
        navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, false);
        navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, true);
        navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, false);
        navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, true);

        Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
        Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;

            assertThrowsIAE(
                () -> navigableSet.subSet(last, true, first, false),
                description
                + ": Must throw IllegalArgumentException when fromElement is not less than toElement.");

        navigableSet.subSet(first, true, last, false);
    }

    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testSubSetRanges(String description, NavigableSet navigableSet) {
        Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
        Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;

        NavigableSet subSet = navigableSet.subSet(first, true, last, true);

        // same subset
        subSet.subSet(first, true, last, true);

        // slightly smaller
        NavigableSet ns = subSet.subSet(first, false, last, false);
        // slight expansion
        assertThrowsIAE(
            () -> ns.subSet(first, true, last, true),
            description + ": Expansion should not be allowed");

        // much smaller
        subSet.subSet(first, false, BigInteger.ONE, false);
    }

    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testheadSetRanges(String description, NavigableSet navigableSet) {
        NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);

        // same subset
        subSet.headSet(BigInteger.ONE, true);

        // slightly smaller
        NavigableSet ns = subSet.headSet(BigInteger.ONE, false);

        // slight expansion
        assertThrowsIAE(
            () -> ns.headSet(BigInteger.ONE, true),
            description + ": Expansion should not be allowed");

        // much smaller
        subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
    }

    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testTailSetRanges(String description, NavigableSet navigableSet) {
        NavigableSet subSet = navigableSet.tailSet(BigInteger.ONE, true);

        // same subset
        subSet.tailSet(BigInteger.ONE, true);

        // slightly smaller
        NavigableSet ns = subSet.tailSet(BigInteger.ONE, false);

        // slight expansion
        assertThrowsIAE(
            () -> ns.tailSet(BigInteger.ONE, true),
            description + ": Expansion should not be allowed");

        // much smaller
        subSet.tailSet(isDescending(subSet) ? BigInteger.ZERO : BigInteger.TEN, false);
    }

    /**
     * Tests the tailSet() method.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testTailSet(String description, NavigableSet navigableSet) {
        assertThrowsNPE(
            () -> navigableSet.tailSet(null),
            description + ": Must throw NullPointerException for null element");

        assertThrowsCCE(
            () -> navigableSet.tailSet(new Object()),
            description);

        NavigableSet ss = navigableSet.tailSet("1", true);

        assertEmptyNavigableSet(ss, description + ": Returned value is not empty navigable set.");
    }

    /**
     * Tests that the array has a size of 0.
     */
    @Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
    public void testToArray(String description, NavigableSet<?> navigableSet) {
        Object[] emptyNavigableSetArray = navigableSet.toArray();

        assertTrue(emptyNavigableSetArray.length == 0, "Returned non-empty Array.");

        emptyNavigableSetArray = new Object[20];

        Object[] result = navigableSet.toArray(emptyNavigableSetArray);

        assertSame(emptyNavigableSetArray, result);

        assertTrue(result[0] == null);
    }

    @DataProvider(name = "NavigableSet<?>", parallel = true)
    public static Iterator<Object[]> navigableSetsProvider() {
        return makeNavigableSets().iterator();
    }

    public static Collection<Object[]> makeNavigableSets() {
        return Arrays.asList(
            new Object[]{"UnmodifiableNavigableSet(TreeSet)", Collections.unmodifiableNavigableSet(new TreeSet())},
            new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet())},
            new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet().descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet().descendingSet())},
            new Object[]{"emptyNavigableSet()", Collections.emptyNavigableSet()},
            new Object[]{"emptyNavigableSet().descendingSet()", Collections.emptyNavigableSet().descendingSet()},
            new Object[]{"emptyNavigableSet().descendingSet().descendingSet()", Collections.emptyNavigableSet().descendingSet().descendingSet()}
        );
    }
}
Revision:	1.11
Committed:	Mon Jan 8 03:12:03 2018 UTC (6 years, 4 months ago) by jsr166
Branch:	MAIN
Changes since 1.10:	+7 -6 lines
Log Message:	organize imports
#	User	Rev	Content
1	jsr166	1.1	/*
2	jsr166	1.6	* Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved.
3	jsr166	1.1	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4			*
5			* This code is free software; you can redistribute it and/or modify it
6			* under the terms of the GNU General Public License version 2 only, as
7			* published by the Free Software Foundation.
8			*
9			* This code is distributed in the hope that it will be useful, but WITHOUT
10			* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11			* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12			* version 2 for more details (a copy is included in the LICENSE file that
13			* accompanied this code).
14			*
15			* You should have received a copy of the GNU General Public License version
16			* 2 along with this work; if not, write to the Free Software Foundation,
17			* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18			*
19			* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20			* or visit www.oracle.com if you need additional information or have any
21			* questions.
22			*/
23
24			/*
25			* @test
26			* @bug 4533691 7129185
27			* @summary Unit test for Collections.emptyNavigableSet
28			* @run testng EmptyNavigableSet
29			*/
30	jsr166	1.11
31			import org.testng.Assert;
32			import org.testng.Assert.ThrowingRunnable;
33			import org.testng.annotations.DataProvider;
34			import org.testng.annotations.Test;
35
36	jsr166	1.1	import java.math.BigInteger;
37			import java.util.Arrays;
38			import java.util.Collection;
39			import java.util.Collections;
40			import java.util.Comparator;
41			import java.util.Iterator;
42	jsr166	1.11	import java.util.NavigableSet;
43	jsr166	1.1	import java.util.NoSuchElementException;
44			import java.util.SortedSet;
45			import java.util.TreeSet;
46	jsr166	1.6
47	jsr166	1.1	import static org.testng.Assert.assertFalse;
48			import static org.testng.Assert.assertSame;
49	jsr166	1.4	import static org.testng.Assert.assertTrue;
50	jsr166	1.1
51			public class EmptyNavigableSet {
52
53			public static <T> void assertInstance(T actual, Class<? extends T> expected) {
54	jsr166	1.7	assertInstance(actual, expected, null);
55	jsr166	1.1	}
56
57			public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {
58			assertTrue(expected.isInstance(actual), ((null != message) ? message : "")
59			+ " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");
60			}
61
62			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj) {
63			assertInstance(obj, NavigableSet.class);
64			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0));
65			}
66
67			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj, String message) {
68			assertInstance(obj, NavigableSet.class, message);
69			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0),
70			((null != message) ? message : "") + " Not empty. ");
71			}
72
73	jsr166	1.6	private <T extends Throwable> void assertThrows(Class<T> throwableClass,
74			ThrowingRunnable runnable,
75			String message) {
76			try {
77			Assert.assertThrows(throwableClass, runnable);
78			} catch (AssertionError e) {
79			throw new AssertionError(String.format("%s%n%s",
80			((null != message) ? message : ""), e.getMessage()), e);
81			}
82			}
83	jsr166	1.1
84	jsr166	1.6	private void assertThrowsCCE(ThrowingRunnable r, String s) {
85			assertThrows(ClassCastException.class, r, s);
86	jsr166	1.1	}
87
88	jsr166	1.6	private void assertThrowsNPE(ThrowingRunnable r, String s) {
89			assertThrows(NullPointerException.class, r, s);
90	jsr166	1.1	}
91
92	jsr166	1.6	private void assertThrowsIAE(ThrowingRunnable r, String s) {
93			assertThrows(IllegalArgumentException.class, r, s);
94			}
95	jsr166	1.1
96	jsr166	1.6	private void assertThrowsNSEE(ThrowingRunnable r, String s) {
97			assertThrows(NoSuchElementException.class, r, s);
98	jsr166	1.1	}
99
100			public static final boolean isDescending(SortedSet<?> set) {
101			if (null == set.comparator()) {
102			// natural order
103			return false;
104			}
105
106			if (Collections.reverseOrder() == set.comparator()) {
107			// reverse natural order.
108			return true;
109			}
110
111			if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {
112			// it's a Collections.reverseOrder(Comparator).
113			return true;
114			}
115
116			throw new IllegalStateException("can't determine ordering for " + set);
117			}
118
119			/**
120			* Tests that the comparator is {@code null}.
121			*/
122			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
123			public void testComparatorIsNull(String description, NavigableSet<?> navigableSet) {
124			Comparator comparator = navigableSet.comparator();
125
126			assertTrue(comparator == null \|\| comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");
127			}
128
129			/**
130			* Tests that contains requires Comparable
131			*/
132			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
133			public void testContainsRequiresComparable(String description, NavigableSet<?> navigableSet) {
134	jsr166	1.9	assertThrowsCCE(
135			() -> navigableSet.contains(new Object()),
136	jsr166	1.10	description + ": Comparable should be required");
137	jsr166	1.1	}
138
139			/**
140			* Tests that the contains method returns {@code false}.
141			*/
142			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
143			public void testContains(String description, NavigableSet<?> navigableSet) {
144			assertFalse(navigableSet.contains(new Integer(1)),
145			description + ": Should not contain any elements.");
146			}
147
148			/**
149			* Tests that the containsAll method returns {@code false}.
150			*/
151			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
152			public void testContainsAll(String description, NavigableSet<?> navigableSet) {
153			TreeSet treeSet = new TreeSet();
154			treeSet.add("1");
155			treeSet.add("2");
156			treeSet.add("3");
157
158			assertFalse(navigableSet.containsAll(treeSet), "Should not contain any elements.");
159			}
160
161			/**
162			* Tests that the iterator is empty.
163			*/
164			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
165			public void testEmptyIterator(String description, NavigableSet<?> navigableSet) {
166			Iterator emptyIterator = navigableSet.iterator();
167
168			assertFalse((emptyIterator != null) && (emptyIterator.hasNext()),
169			"The iterator is not empty.");
170			}
171
172			/**
173			* Tests that the set is empty.
174			*/
175			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
176			public void testIsEmpty(String description, NavigableSet<?> navigableSet) {
177			assertTrue(navigableSet.isEmpty(), "The set is not empty.");
178			}
179
180			/**
181			* Tests that the first() method throws NoSuchElementException
182			*/
183			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
184			public void testFirst(String description, NavigableSet<?> navigableSet) {
185	jsr166	1.8	assertThrowsNSEE(navigableSet::first, description);
186	jsr166	1.1	}
187
188			/**
189			* Tests the headSet() method.
190			*/
191			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
192			public void testHeadSet(String description, NavigableSet navigableSet) {
193	jsr166	1.6	assertThrowsNPE(
194	jsr166	1.1	() -> { NavigableSet ns = navigableSet.headSet(null, false); },
195			description + ": Must throw NullPointerException for null element");
196
197	jsr166	1.6	assertThrowsCCE(
198	jsr166	1.1	() -> { NavigableSet ns = navigableSet.headSet(new Object(), true); },
199			description + ": Must throw ClassCastException for non-Comparable element");
200
201			NavigableSet ns = navigableSet.headSet("1", false);
202
203			assertEmptyNavigableSet(ns, description + ": Returned value is not empty navigable set.");
204			}
205
206			/**
207			* Tests that the last() method throws NoSuchElementException
208			*/
209			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
210			public void testLast(String description, NavigableSet<?> navigableSet) {
211	jsr166	1.8	assertThrowsNSEE(navigableSet::last, description);
212	jsr166	1.1	}
213
214			/**
215			* Tests that the size is 0.
216			*/
217			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
218			public void testSizeIsZero(String description, NavigableSet<?> navigableSet) {
219			assertTrue(0 == navigableSet.size(), "The size of the set is not 0.");
220			}
221
222			/**
223			* Tests the subSet() method.
224			*/
225			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
226			public void testSubSet(String description, NavigableSet navigableSet) {
227	jsr166	1.6	assertThrowsNPE(
228	jsr166	1.1	() -> {
229			SortedSet ss = navigableSet.subSet(null, BigInteger.TEN);
230			},
231			description + ": Must throw NullPointerException for null element");
232
233	jsr166	1.6	assertThrowsNPE(
234	jsr166	1.1	() -> {
235			SortedSet ss = navigableSet.subSet(BigInteger.ZERO, null);
236			},
237			description + ": Must throw NullPointerException for null element");
238
239	jsr166	1.6	assertThrowsNPE(
240	jsr166	1.1	() -> {
241			SortedSet ss = navigableSet.subSet(null, null);
242			},
243			description + ": Must throw NullPointerException for null element");
244
245			Object obj1 = new Object();
246			Object obj2 = new Object();
247
248	jsr166	1.6	assertThrowsCCE(
249	jsr166	1.1	() -> {
250			SortedSet ss = navigableSet.subSet(obj1, BigInteger.TEN);
251			},
252	jsr166	1.6	description + ": Must throw ClassCastException for parameter which is not Comparable.");
253	jsr166	1.1
254	jsr166	1.6	assertThrowsCCE(
255	jsr166	1.1	() -> {
256			SortedSet ss = navigableSet.subSet(BigInteger.ZERO, obj2);
257			},
258	jsr166	1.6	description + ": Must throw ClassCastException for parameter which is not Comparable.");
259	jsr166	1.1
260	jsr166	1.6	assertThrowsCCE(
261	jsr166	1.1	() -> {
262			SortedSet ss = navigableSet.subSet(obj1, obj2);
263			},
264	jsr166	1.6	description + ": Must throw ClassCastException for parameter which is not Comparable.");
265	jsr166	1.1
266			// minimal range
267			navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, false);
268			navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, true);
269			navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, false);
270			navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, true);
271
272			Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
273			Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
274
275	jsr166	1.6	assertThrowsIAE(
276	jsr166	1.9	() -> navigableSet.subSet(last, true, first, false),
277	jsr166	1.6	description
278	jsr166	1.3	+ ": Must throw IllegalArgumentException when fromElement is not less than toElement.");
279	jsr166	1.1
280			navigableSet.subSet(first, true, last, false);
281			}
282
283			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
284			public void testSubSetRanges(String description, NavigableSet navigableSet) {
285			Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
286			Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
287
288			NavigableSet subSet = navigableSet.subSet(first, true, last, true);
289
290			// same subset
291			subSet.subSet(first, true, last, true);
292
293			// slightly smaller
294			NavigableSet ns = subSet.subSet(first, false, last, false);
295	jsr166	1.2	// slight expansion
296	jsr166	1.9	assertThrowsIAE(
297			() -> ns.subSet(first, true, last, true),
298	jsr166	1.1	description + ": Expansion should not be allowed");
299
300			// much smaller
301			subSet.subSet(first, false, BigInteger.ONE, false);
302			}
303
304			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
305			public void testheadSetRanges(String description, NavigableSet navigableSet) {
306			NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
307
308			// same subset
309			subSet.headSet(BigInteger.ONE, true);
310
311			// slightly smaller
312			NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
313
314	jsr166	1.2	// slight expansion
315	jsr166	1.9	assertThrowsIAE(
316			() -> ns.headSet(BigInteger.ONE, true),
317	jsr166	1.1	description + ": Expansion should not be allowed");
318
319			// much smaller
320			subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
321			}
322
323			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
324			public void testTailSetRanges(String description, NavigableSet navigableSet) {
325			NavigableSet subSet = navigableSet.tailSet(BigInteger.ONE, true);
326
327			// same subset
328			subSet.tailSet(BigInteger.ONE, true);
329
330			// slightly smaller
331			NavigableSet ns = subSet.tailSet(BigInteger.ONE, false);
332
333	jsr166	1.2	// slight expansion
334	jsr166	1.9	assertThrowsIAE(
335			() -> ns.tailSet(BigInteger.ONE, true),
336	jsr166	1.1	description + ": Expansion should not be allowed");
337
338			// much smaller
339			subSet.tailSet(isDescending(subSet) ? BigInteger.ZERO : BigInteger.TEN, false);
340			}
341
342			/**
343			* Tests the tailSet() method.
344			*/
345			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
346			public void testTailSet(String description, NavigableSet navigableSet) {
347	jsr166	1.9	assertThrowsNPE(
348			() -> navigableSet.tailSet(null),
349	jsr166	1.1	description + ": Must throw NullPointerException for null element");
350
351	jsr166	1.9	assertThrowsCCE(
352			() -> navigableSet.tailSet(new Object()),
353			description);
354	jsr166	1.1
355			NavigableSet ss = navigableSet.tailSet("1", true);
356
357			assertEmptyNavigableSet(ss, description + ": Returned value is not empty navigable set.");
358			}
359
360			/**
361			* Tests that the array has a size of 0.
362			*/
363			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
364			public void testToArray(String description, NavigableSet<?> navigableSet) {
365			Object[] emptyNavigableSetArray = navigableSet.toArray();
366
367			assertTrue(emptyNavigableSetArray.length == 0, "Returned non-empty Array.");
368
369			emptyNavigableSetArray = new Object[20];
370
371			Object[] result = navigableSet.toArray(emptyNavigableSetArray);
372
373			assertSame(emptyNavigableSetArray, result);
374
375			assertTrue(result[0] == null);
376			}
377
378			@DataProvider(name = "NavigableSet<?>", parallel = true)
379			public static Iterator<Object[]> navigableSetsProvider() {
380			return makeNavigableSets().iterator();
381			}
382
383			public static Collection<Object[]> makeNavigableSets() {
384			return Arrays.asList(
385			new Object[]{"UnmodifiableNavigableSet(TreeSet)", Collections.unmodifiableNavigableSet(new TreeSet())},
386			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet())},
387			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet().descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet().descendingSet())},
388			new Object[]{"emptyNavigableSet()", Collections.emptyNavigableSet()},
389			new Object[]{"emptyNavigableSet().descendingSet()", Collections.emptyNavigableSet().descendingSet()},
390			new Object[]{"emptyNavigableSet().descendingSet().descendingSet()", Collections.emptyNavigableSet().descendingSet().descendingSet()}
391			);
392			}
393			}