util/Collections/EmptyNavigableSet.java

/*
 * Copyright (c) 2011, 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.
 */

/*
 * @test
 * @bug 4533691 7129185
 * @summary Unit test for Collections.emptyNavigableSet
 * @run testng EmptyNavigableSet
 */
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.NoSuchElementException;
import java.util.NavigableSet;
import java.util.SortedSet;
import java.util.TreeSet;
import org.testng.annotations.Test;
import org.testng.annotations.DataProvider;

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

public class EmptyNavigableSet {

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

    public interface Thrower<T extends Throwable> {

        public void run() throws T;
    }

    public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable) {
        assertThrows(thrower, throwable, null);
    }

    public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable, String message) {
        Throwable result;
        try {
            thrower.run();
            fail(((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");
            return;
        } catch (Throwable caught) {
            result = caught;
        }

        assertInstance(result, throwable, ((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");
    }

    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) {
        assertThrows(() -> {
            navigableSet.contains(new Object());
        },
            ClassCastException.class,
            description + ": Compareable 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) {
        assertThrows(() -> {
            navigableSet.first();
        }, NoSuchElementException.class, description);
    }

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

        assertThrows(
            () -> { NavigableSet ns = navigableSet.headSet(new Object(), true); },
            ClassCastException.class,
            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) {
        assertThrows(() -> {
            navigableSet.last();
        }, NoSuchElementException.class, 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) {
        assertThrows(
            () -> {
                SortedSet ss = navigableSet.subSet(null, BigInteger.TEN);
            },
            NullPointerException.class,
            description + ": Must throw NullPointerException for null element");

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

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

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

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

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

        assertThrows(
            () -> {
                SortedSet ss = navigableSet.subSet(obj1, obj2);
            },
            ClassCastException.class, 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;

            assertThrows(
                () -> {
                    navigableSet.subSet(last, true, first, false);
                },
                IllegalArgumentException.class, 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
        assertThrows(() -> {
            ns.subSet(first, true, last, true);
        },
            IllegalArgumentException.class,
            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
        assertThrows(() -> {
            ns.headSet(BigInteger.ONE, true);
        },
            IllegalArgumentException.class,
            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
        assertThrows(() -> {
            ns.tailSet(BigInteger.ONE, true);
        },
            IllegalArgumentException.class,
            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) {
        assertThrows(() -> {
            navigableSet.tailSet(null);
        },
            NullPointerException.class,
            description + ": Must throw NullPointerException for null element");

        assertThrows(() -> {
            navigableSet.tailSet(new Object());
        }, ClassCastException.class);

        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:	1.3
Committed:	Mon Feb 8 22:13:07 2016 UTC (8 years, 3 months ago) by jsr166
Branch:	MAIN
Changes since 1.2:	+1 -1 lines
Log Message:	import 8138838: docs cleanup for java.desktop
#	User	Rev	Content
1	jsr166	1.1	/*
2			* Copyright (c) 2011, 2013, 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			import java.math.BigInteger;
31			import java.util.Arrays;
32			import java.util.Collection;
33			import java.util.Collections;
34			import java.util.Comparator;
35			import java.util.Iterator;
36			import java.util.NoSuchElementException;
37			import java.util.NavigableSet;
38			import java.util.SortedSet;
39			import java.util.TreeSet;
40			import org.testng.annotations.Test;
41			import org.testng.annotations.DataProvider;
42
43			import static org.testng.Assert.fail;
44			import static org.testng.Assert.assertEquals;
45			import static org.testng.Assert.assertTrue;
46			import static org.testng.Assert.assertFalse;
47			import static org.testng.Assert.assertSame;
48
49			public class EmptyNavigableSet {
50
51			public static <T> void assertInstance(T actual, Class<? extends T> expected) {
52			assertInstance(expected.isInstance(actual), null);
53			}
54
55			public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {
56			assertTrue(expected.isInstance(actual), ((null != message) ? message : "")
57			+ " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");
58			}
59
60			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj) {
61			assertInstance(obj, NavigableSet.class);
62			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0));
63			}
64
65			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj, String message) {
66			assertInstance(obj, NavigableSet.class, message);
67			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0),
68			((null != message) ? message : "") + " Not empty. ");
69			}
70
71			public interface Thrower<T extends Throwable> {
72
73			public void run() throws T;
74			}
75
76			public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable) {
77			assertThrows(thrower, throwable, null);
78			}
79
80			public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable, String message) {
81			Throwable result;
82			try {
83			thrower.run();
84			fail(((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");
85			return;
86			} catch (Throwable caught) {
87			result = caught;
88			}
89
90			assertInstance(result, throwable, ((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");
91			}
92
93			public static final boolean isDescending(SortedSet<?> set) {
94			if (null == set.comparator()) {
95			// natural order
96			return false;
97			}
98
99			if (Collections.reverseOrder() == set.comparator()) {
100			// reverse natural order.
101			return true;
102			}
103
104			if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {
105			// it's a Collections.reverseOrder(Comparator).
106			return true;
107			}
108
109			throw new IllegalStateException("can't determine ordering for " + set);
110			}
111
112			/**
113			* Tests that the comparator is {@code null}.
114			*/
115			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
116			public void testComparatorIsNull(String description, NavigableSet<?> navigableSet) {
117			Comparator comparator = navigableSet.comparator();
118
119			assertTrue(comparator == null \|\| comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");
120			}
121
122			/**
123			* Tests that contains requires Comparable
124			*/
125			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
126			public void testContainsRequiresComparable(String description, NavigableSet<?> navigableSet) {
127			assertThrows(() -> {
128			navigableSet.contains(new Object());
129			},
130			ClassCastException.class,
131			description + ": Compareable should be required");
132			}
133
134			/**
135			* Tests that the contains method returns {@code false}.
136			*/
137			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
138			public void testContains(String description, NavigableSet<?> navigableSet) {
139			assertFalse(navigableSet.contains(new Integer(1)),
140			description + ": Should not contain any elements.");
141			}
142
143			/**
144			* Tests that the containsAll method returns {@code false}.
145			*/
146			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
147			public void testContainsAll(String description, NavigableSet<?> navigableSet) {
148			TreeSet treeSet = new TreeSet();
149			treeSet.add("1");
150			treeSet.add("2");
151			treeSet.add("3");
152
153			assertFalse(navigableSet.containsAll(treeSet), "Should not contain any elements.");
154			}
155
156			/**
157			* Tests that the iterator is empty.
158			*/
159			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
160			public void testEmptyIterator(String description, NavigableSet<?> navigableSet) {
161			Iterator emptyIterator = navigableSet.iterator();
162
163			assertFalse((emptyIterator != null) && (emptyIterator.hasNext()),
164			"The iterator is not empty.");
165			}
166
167			/**
168			* Tests that the set is empty.
169			*/
170			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
171			public void testIsEmpty(String description, NavigableSet<?> navigableSet) {
172			assertTrue(navigableSet.isEmpty(), "The set is not empty.");
173			}
174
175			/**
176			* Tests that the first() method throws NoSuchElementException
177			*/
178			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
179			public void testFirst(String description, NavigableSet<?> navigableSet) {
180			assertThrows(() -> {
181			navigableSet.first();
182			}, NoSuchElementException.class, description);
183			}
184
185			/**
186			* Tests the headSet() method.
187			*/
188			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
189			public void testHeadSet(String description, NavigableSet navigableSet) {
190			assertThrows(
191			() -> { NavigableSet ns = navigableSet.headSet(null, false); },
192			NullPointerException.class,
193			description + ": Must throw NullPointerException for null element");
194
195			assertThrows(
196			() -> { NavigableSet ns = navigableSet.headSet(new Object(), true); },
197			ClassCastException.class,
198			description + ": Must throw ClassCastException for non-Comparable element");
199
200			NavigableSet ns = navigableSet.headSet("1", false);
201
202			assertEmptyNavigableSet(ns, description + ": Returned value is not empty navigable set.");
203			}
204
205			/**
206			* Tests that the last() method throws NoSuchElementException
207			*/
208			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
209			public void testLast(String description, NavigableSet<?> navigableSet) {
210			assertThrows(() -> {
211			navigableSet.last();
212			}, NoSuchElementException.class, description);
213			}
214
215			/**
216			* Tests that the size is 0.
217			*/
218			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
219			public void testSizeIsZero(String description, NavigableSet<?> navigableSet) {
220			assertTrue(0 == navigableSet.size(), "The size of the set is not 0.");
221			}
222
223			/**
224			* Tests the subSet() method.
225			*/
226			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
227			public void testSubSet(String description, NavigableSet navigableSet) {
228			assertThrows(
229			() -> {
230			SortedSet ss = navigableSet.subSet(null, BigInteger.TEN);
231			},
232			NullPointerException.class,
233			description + ": Must throw NullPointerException for null element");
234
235			assertThrows(
236			() -> {
237			SortedSet ss = navigableSet.subSet(BigInteger.ZERO, null);
238			},
239			NullPointerException.class,
240			description + ": Must throw NullPointerException for null element");
241
242			assertThrows(
243			() -> {
244			SortedSet ss = navigableSet.subSet(null, null);
245			},
246			NullPointerException.class,
247			description + ": Must throw NullPointerException for null element");
248
249			Object obj1 = new Object();
250			Object obj2 = new Object();
251
252			assertThrows(
253			() -> {
254			SortedSet ss = navigableSet.subSet(obj1, BigInteger.TEN);
255			},
256			ClassCastException.class, description
257			+ ": Must throw ClassCastException for parameter which is not Comparable.");
258
259			assertThrows(
260			() -> {
261			SortedSet ss = navigableSet.subSet(BigInteger.ZERO, obj2);
262			},
263			ClassCastException.class, description
264			+ ": Must throw ClassCastException for parameter which is not Comparable.");
265
266			assertThrows(
267			() -> {
268			SortedSet ss = navigableSet.subSet(obj1, obj2);
269			},
270			ClassCastException.class, description
271			+ ": Must throw ClassCastException for parameter which is not Comparable.");
272
273			// minimal range
274			navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, false);
275			navigableSet.subSet(BigInteger.ZERO, false, BigInteger.ZERO, true);
276			navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, false);
277			navigableSet.subSet(BigInteger.ZERO, true, BigInteger.ZERO, true);
278
279			Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
280			Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
281
282			assertThrows(
283			() -> {
284			navigableSet.subSet(last, true, first, false);
285			},
286			IllegalArgumentException.class, description
287	jsr166	1.3	+ ": Must throw IllegalArgumentException when fromElement is not less than toElement.");
288	jsr166	1.1
289			navigableSet.subSet(first, true, last, false);
290			}
291
292			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
293			public void testSubSetRanges(String description, NavigableSet navigableSet) {
294			Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
295			Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
296
297			NavigableSet subSet = navigableSet.subSet(first, true, last, true);
298
299			// same subset
300			subSet.subSet(first, true, last, true);
301
302			// slightly smaller
303			NavigableSet ns = subSet.subSet(first, false, last, false);
304	jsr166	1.2	// slight expansion
305	jsr166	1.1	assertThrows(() -> {
306			ns.subSet(first, true, last, true);
307			},
308			IllegalArgumentException.class,
309			description + ": Expansion should not be allowed");
310
311			// much smaller
312			subSet.subSet(first, false, BigInteger.ONE, false);
313			}
314
315			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
316			public void testheadSetRanges(String description, NavigableSet navigableSet) {
317			NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
318
319			// same subset
320			subSet.headSet(BigInteger.ONE, true);
321
322			// slightly smaller
323			NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
324
325	jsr166	1.2	// slight expansion
326	jsr166	1.1	assertThrows(() -> {
327			ns.headSet(BigInteger.ONE, true);
328			},
329			IllegalArgumentException.class,
330			description + ": Expansion should not be allowed");
331
332			// much smaller
333			subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
334			}
335
336			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
337			public void testTailSetRanges(String description, NavigableSet navigableSet) {
338			NavigableSet subSet = navigableSet.tailSet(BigInteger.ONE, true);
339
340			// same subset
341			subSet.tailSet(BigInteger.ONE, true);
342
343			// slightly smaller
344			NavigableSet ns = subSet.tailSet(BigInteger.ONE, false);
345
346	jsr166	1.2	// slight expansion
347	jsr166	1.1	assertThrows(() -> {
348			ns.tailSet(BigInteger.ONE, true);
349			},
350			IllegalArgumentException.class,
351			description + ": Expansion should not be allowed");
352
353			// much smaller
354			subSet.tailSet(isDescending(subSet) ? BigInteger.ZERO : BigInteger.TEN, false);
355			}
356
357			/**
358			* Tests the tailSet() method.
359			*/
360			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
361			public void testTailSet(String description, NavigableSet navigableSet) {
362			assertThrows(() -> {
363			navigableSet.tailSet(null);
364			},
365			NullPointerException.class,
366			description + ": Must throw NullPointerException for null element");
367
368			assertThrows(() -> {
369			navigableSet.tailSet(new Object());
370			}, ClassCastException.class);
371
372			NavigableSet ss = navigableSet.tailSet("1", true);
373
374			assertEmptyNavigableSet(ss, description + ": Returned value is not empty navigable set.");
375			}
376
377			/**
378			* Tests that the array has a size of 0.
379			*/
380			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
381			public void testToArray(String description, NavigableSet<?> navigableSet) {
382			Object[] emptyNavigableSetArray = navigableSet.toArray();
383
384			assertTrue(emptyNavigableSetArray.length == 0, "Returned non-empty Array.");
385
386			emptyNavigableSetArray = new Object[20];
387
388			Object[] result = navigableSet.toArray(emptyNavigableSetArray);
389
390			assertSame(emptyNavigableSetArray, result);
391
392			assertTrue(result[0] == null);
393			}
394
395			@DataProvider(name = "NavigableSet<?>", parallel = true)
396			public static Iterator<Object[]> navigableSetsProvider() {
397			return makeNavigableSets().iterator();
398			}
399
400			public static Collection<Object[]> makeNavigableSets() {
401			return Arrays.asList(
402			new Object[]{"UnmodifiableNavigableSet(TreeSet)", Collections.unmodifiableNavigableSet(new TreeSet())},
403			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet())},
404			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet().descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet().descendingSet())},
405			new Object[]{"emptyNavigableSet()", Collections.emptyNavigableSet()},
406			new Object[]{"emptyNavigableSet().descendingSet()", Collections.emptyNavigableSet().descendingSet()},
407			new Object[]{"emptyNavigableSet().descendingSet().descendingSet()", Collections.emptyNavigableSet().descendingSet().descendingSet()}
408			);
409			}
410			}