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.assertNull;
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) {
        assertFalse(navigableSet.iterator().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);

        assertNull(result[0]);
    }

    @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:	1.14
Committed:	Mon Jul 23 01:11:22 2018 UTC (5 years, 9 months ago) by jsr166
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.13:	+1 -0 lines
Log Message:	fix imports
#	Content
1	/*
2	* Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved.
3	* 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
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	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	import java.util.NavigableSet;
43	import java.util.NoSuchElementException;
44	import java.util.SortedSet;
45	import java.util.TreeSet;
46
47	import static org.testng.Assert.assertFalse;
48	import static org.testng.Assert.assertNull;
49	import static org.testng.Assert.assertSame;
50	import static org.testng.Assert.assertTrue;
51
52	public class EmptyNavigableSet {
53
54	public static <T> void assertInstance(T actual, Class<? extends T> expected) {
55	assertInstance(actual, expected, null);
56	}
57
58	public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {
59	assertTrue(expected.isInstance(actual), ((null != message) ? message : "")
60	+ " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");
61	}
62
63	public static <T extends Throwable> void assertEmptyNavigableSet(Object obj) {
64	assertInstance(obj, NavigableSet.class);
65	assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0));
66	}
67
68	public static <T extends Throwable> void assertEmptyNavigableSet(Object obj, String message) {
69	assertInstance(obj, NavigableSet.class, message);
70	assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0),
71	((null != message) ? message : "") + " Not empty. ");
72	}
73
74	private <T extends Throwable> void assertThrows(Class<T> throwableClass,
75	ThrowingRunnable runnable,
76	String message) {
77	try {
78	Assert.assertThrows(throwableClass, runnable);
79	} catch (AssertionError e) {
80	throw new AssertionError(String.format("%s%n%s",
81	((null != message) ? message : ""), e.getMessage()), e);
82	}
83	}
84
85	private void assertThrowsCCE(ThrowingRunnable r, String s) {
86	assertThrows(ClassCastException.class, r, s);
87	}
88
89	private void assertThrowsNPE(ThrowingRunnable r, String s) {
90	assertThrows(NullPointerException.class, r, s);
91	}
92
93	private void assertThrowsIAE(ThrowingRunnable r, String s) {
94	assertThrows(IllegalArgumentException.class, r, s);
95	}
96
97	private void assertThrowsNSEE(ThrowingRunnable r, String s) {
98	assertThrows(NoSuchElementException.class, r, s);
99	}
100
101	public static final boolean isDescending(SortedSet<?> set) {
102	if (null == set.comparator()) {
103	// natural order
104	return false;
105	}
106
107	if (Collections.reverseOrder() == set.comparator()) {
108	// reverse natural order.
109	return true;
110	}
111
112	if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {
113	// it's a Collections.reverseOrder(Comparator).
114	return true;
115	}
116
117	throw new IllegalStateException("can't determine ordering for " + set);
118	}
119
120	/**
121	* Tests that the comparator is {@code null}.
122	*/
123	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
124	public void testComparatorIsNull(String description, NavigableSet<?> navigableSet) {
125	Comparator comparator = navigableSet.comparator();
126
127	assertTrue(comparator == null \|\| comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");
128	}
129
130	/**
131	* Tests that contains requires Comparable
132	*/
133	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
134	public void testContainsRequiresComparable(String description, NavigableSet<?> navigableSet) {
135	assertThrowsCCE(
136	() -> navigableSet.contains(new Object()),
137	description + ": Comparable should be required");
138	}
139
140	/**
141	* Tests that the contains method returns {@code false}.
142	*/
143	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
144	public void testContains(String description, NavigableSet<?> navigableSet) {
145	assertFalse(navigableSet.contains(new Integer(1)),
146	description + ": Should not contain any elements.");
147	}
148
149	/**
150	* Tests that the containsAll method returns {@code false}.
151	*/
152	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
153	public void testContainsAll(String description, NavigableSet<?> navigableSet) {
154	TreeSet treeSet = new TreeSet();
155	treeSet.add("1");
156	treeSet.add("2");
157	treeSet.add("3");
158
159	assertFalse(navigableSet.containsAll(treeSet), "Should not contain any elements.");
160	}
161
162	/**
163	* Tests that the iterator is empty.
164	*/
165	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
166	public void testEmptyIterator(String description, NavigableSet<?> navigableSet) {
167	assertFalse(navigableSet.iterator().hasNext(), "The iterator is not empty.");
168	}
169
170	/**
171	* Tests that the set is empty.
172	*/
173	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
174	public void testIsEmpty(String description, NavigableSet<?> navigableSet) {
175	assertTrue(navigableSet.isEmpty(), "The set is not empty.");
176	}
177
178	/**
179	* Tests that the first() method throws NoSuchElementException
180	*/
181	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
182	public void testFirst(String description, NavigableSet<?> navigableSet) {
183	assertThrowsNSEE(navigableSet::first, description);
184	}
185
186	/**
187	* Tests the headSet() method.
188	*/
189	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
190	public void testHeadSet(String description, NavigableSet navigableSet) {
191	assertThrowsNPE(
192	() -> { NavigableSet ns = navigableSet.headSet(null, false); },
193	description + ": Must throw NullPointerException for null element");
194
195	assertThrowsCCE(
196	() -> { NavigableSet ns = navigableSet.headSet(new Object(), true); },
197	description + ": Must throw ClassCastException for non-Comparable element");
198
199	NavigableSet ns = navigableSet.headSet("1", false);
200
201	assertEmptyNavigableSet(ns, description + ": Returned value is not empty navigable set.");
202	}
203
204	/**
205	* Tests that the last() method throws NoSuchElementException
206	*/
207	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
208	public void testLast(String description, NavigableSet<?> navigableSet) {
209	assertThrowsNSEE(navigableSet::last, description);
210	}
211
212	/**
213	* Tests that the size is 0.
214	*/
215	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
216	public void testSizeIsZero(String description, NavigableSet<?> navigableSet) {
217	assertTrue(0 == navigableSet.size(), "The size of the set is not 0.");
218	}
219
220	/**
221	* Tests the subSet() method.
222	*/
223	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
224	public void testSubSet(String description, NavigableSet navigableSet) {
225	assertThrowsNPE(
226	() -> {
227	SortedSet ss = navigableSet.subSet(null, BigInteger.TEN);
228	},
229	description + ": Must throw NullPointerException for null element");
230
231	assertThrowsNPE(
232	() -> {
233	SortedSet ss = navigableSet.subSet(BigInteger.ZERO, null);
234	},
235	description + ": Must throw NullPointerException for null element");
236
237	assertThrowsNPE(
238	() -> {
239	SortedSet ss = navigableSet.subSet(null, null);
240	},
241	description + ": Must throw NullPointerException for null element");
242
243	Object obj1 = new Object();
244	Object obj2 = new Object();
245
246	assertThrowsCCE(
247	() -> {
248	SortedSet ss = navigableSet.subSet(obj1, BigInteger.TEN);
249	},
250	description + ": Must throw ClassCastException for parameter which is not Comparable.");
251
252	assertThrowsCCE(
253	() -> {
254	SortedSet ss = navigableSet.subSet(BigInteger.ZERO, obj2);
255	},
256	description + ": Must throw ClassCastException for parameter which is not Comparable.");
257
258	assertThrowsCCE(
259	() -> {
260	SortedSet ss = navigableSet.subSet(obj1, obj2);
261	},
262	description + ": Must throw ClassCastException for parameter which is not Comparable.");
263
264	// minimal range
265	navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, false);
266	navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, true);
267	navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, false);
268	navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, true);
269
270	Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
271	Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
272
273	assertThrowsIAE(
274	() -> navigableSet.subSet(last, true, first, false),
275	description
276	+ ": Must throw IllegalArgumentException when fromElement is not less than toElement.");
277
278	navigableSet.subSet(first, true, last, false);
279	}
280
281	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
282	public void testSubSetRanges(String description, NavigableSet navigableSet) {
283	Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
284	Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
285
286	NavigableSet subSet = navigableSet.subSet(first, true, last, true);
287
288	// same subset
289	subSet.subSet(first, true, last, true);
290
291	// slightly smaller
292	NavigableSet ns = subSet.subSet(first, false, last, false);
293	// slight expansion
294	assertThrowsIAE(
295	() -> ns.subSet(first, true, last, true),
296	description + ": Expansion should not be allowed");
297
298	// much smaller
299	subSet.subSet(first, false, BigInteger.ONE, false);
300	}
301
302	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
303	public void testheadSetRanges(String description, NavigableSet navigableSet) {
304	NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
305
306	// same subset
307	subSet.headSet(BigInteger.ONE, true);
308
309	// slightly smaller
310	NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
311
312	// slight expansion
313	assertThrowsIAE(
314	() -> ns.headSet(BigInteger.ONE, true),
315	description + ": Expansion should not be allowed");
316
317	// much smaller
318	subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
319	}
320
321	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
322	public void testTailSetRanges(String description, NavigableSet navigableSet) {
323	NavigableSet subSet = navigableSet.tailSet(BigInteger.ONE, true);
324
325	// same subset
326	subSet.tailSet(BigInteger.ONE, true);
327
328	// slightly smaller
329	NavigableSet ns = subSet.tailSet(BigInteger.ONE, false);
330
331	// slight expansion
332	assertThrowsIAE(
333	() -> ns.tailSet(BigInteger.ONE, true),
334	description + ": Expansion should not be allowed");
335
336	// much smaller
337	subSet.tailSet(isDescending(subSet) ? BigInteger.ZERO : BigInteger.TEN, false);
338	}
339
340	/**
341	* Tests the tailSet() method.
342	*/
343	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
344	public void testTailSet(String description, NavigableSet navigableSet) {
345	assertThrowsNPE(
346	() -> navigableSet.tailSet(null),
347	description + ": Must throw NullPointerException for null element");
348
349	assertThrowsCCE(
350	() -> navigableSet.tailSet(new Object()),
351	description);
352
353	NavigableSet ss = navigableSet.tailSet("1", true);
354
355	assertEmptyNavigableSet(ss, description + ": Returned value is not empty navigable set.");
356	}
357
358	/**
359	* Tests that the array has a size of 0.
360	*/
361	@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
362	public void testToArray(String description, NavigableSet<?> navigableSet) {
363	Object[] emptyNavigableSetArray = navigableSet.toArray();
364
365	assertTrue(emptyNavigableSetArray.length == 0, "Returned non-empty Array.");
366
367	emptyNavigableSetArray = new Object[20];
368
369	Object[] result = navigableSet.toArray(emptyNavigableSetArray);
370
371	assertSame(emptyNavigableSetArray, result);
372
373	assertNull(result[0]);
374	}
375
376	@DataProvider(name = "NavigableSet<?>", parallel = true)
377	public static Iterator<Object[]> navigableSetsProvider() {
378	return makeNavigableSets().iterator();
379	}
380
381	public static Collection<Object[]> makeNavigableSets() {
382	return Arrays.asList(
383	new Object[]{"UnmodifiableNavigableSet(TreeSet)", Collections.unmodifiableNavigableSet(new TreeSet())},
384	new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet())},
385	new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet().descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet().descendingSet())},
386	new Object[]{"emptyNavigableSet()", Collections.emptyNavigableSet()},
387	new Object[]{"emptyNavigableSet().descendingSet()", Collections.emptyNavigableSet().descendingSet()},
388	new Object[]{"emptyNavigableSet().descendingSet().descendingSet()", Collections.emptyNavigableSet().descendingSet().descendingSet()}
389	);
390	}
391	}