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

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 + ": 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) {
        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:	1.8
Committed:	Sun Jan 7 23:26:04 2018 UTC (6 years, 4 months ago) by jsr166
Branch:	MAIN
Changes since 1.7:	+2 -6 lines
Log Message:	use method references
#	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			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	jsr166	1.6
41			import org.testng.Assert;
42			import org.testng.Assert.ThrowingRunnable;
43	jsr166	1.1	import org.testng.annotations.Test;
44			import org.testng.annotations.DataProvider;
45
46			import static org.testng.Assert.assertFalse;
47			import static org.testng.Assert.assertSame;
48	jsr166	1.4	import static org.testng.Assert.assertTrue;
49	jsr166	1.1
50			public class EmptyNavigableSet {
51
52			public static <T> void assertInstance(T actual, Class<? extends T> expected) {
53	jsr166	1.7	assertInstance(actual, expected, null);
54	jsr166	1.1	}
55
56			public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {
57			assertTrue(expected.isInstance(actual), ((null != message) ? message : "")
58			+ " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");
59			}
60
61			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj) {
62			assertInstance(obj, NavigableSet.class);
63			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0));
64			}
65
66			public static <T extends Throwable> void assertEmptyNavigableSet(Object obj, String message) {
67			assertInstance(obj, NavigableSet.class, message);
68			assertTrue(((NavigableSet)obj).isEmpty() && (((NavigableSet)obj).size() == 0),
69			((null != message) ? message : "") + " Not empty. ");
70			}
71
72	jsr166	1.6	private <T extends Throwable> void assertThrows(Class<T> throwableClass,
73			ThrowingRunnable runnable,
74			String message) {
75			try {
76			Assert.assertThrows(throwableClass, runnable);
77			} catch (AssertionError e) {
78			throw new AssertionError(String.format("%s%n%s",
79			((null != message) ? message : ""), e.getMessage()), e);
80			}
81			}
82	jsr166	1.1
83	jsr166	1.6	private void assertThrowsCCE(ThrowingRunnable r, String s) {
84			assertThrows(ClassCastException.class, r, s);
85	jsr166	1.1	}
86
87	jsr166	1.6	private void assertThrowsNPE(ThrowingRunnable r, String s) {
88			assertThrows(NullPointerException.class, r, s);
89	jsr166	1.1	}
90
91	jsr166	1.6	private void assertThrowsIAE(ThrowingRunnable r, String s) {
92			assertThrows(IllegalArgumentException.class, r, s);
93			}
94	jsr166	1.1
95	jsr166	1.6	private void assertThrowsNSEE(ThrowingRunnable r, String s) {
96			assertThrows(NoSuchElementException.class, r, s);
97	jsr166	1.1	}
98
99			public static final boolean isDescending(SortedSet<?> set) {
100			if (null == set.comparator()) {
101			// natural order
102			return false;
103			}
104
105			if (Collections.reverseOrder() == set.comparator()) {
106			// reverse natural order.
107			return true;
108			}
109
110			if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {
111			// it's a Collections.reverseOrder(Comparator).
112			return true;
113			}
114
115			throw new IllegalStateException("can't determine ordering for " + set);
116			}
117
118			/**
119			* Tests that the comparator is {@code null}.
120			*/
121			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
122			public void testComparatorIsNull(String description, NavigableSet<?> navigableSet) {
123			Comparator comparator = navigableSet.comparator();
124
125			assertTrue(comparator == null \|\| comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");
126			}
127
128			/**
129			* Tests that contains requires Comparable
130			*/
131			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
132			public void testContainsRequiresComparable(String description, NavigableSet<?> navigableSet) {
133	jsr166	1.6	assertThrowsCCE(() -> {
134	jsr166	1.1	navigableSet.contains(new Object());
135			},
136	jsr166	1.6	description + ": Compareable 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	1.1	() -> {
277			navigableSet.subSet(last, true, first, false);
278			},
279	jsr166	1.6	description
280	jsr166	1.3	+ ": Must throw IllegalArgumentException when fromElement is not less than toElement.");
281	jsr166	1.1
282			navigableSet.subSet(first, true, last, false);
283			}
284
285			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
286			public void testSubSetRanges(String description, NavigableSet navigableSet) {
287			Object first = isDescending(navigableSet) ? BigInteger.TEN : BigInteger.ZERO;
288			Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;
289
290			NavigableSet subSet = navigableSet.subSet(first, true, last, true);
291
292			// same subset
293			subSet.subSet(first, true, last, true);
294
295			// slightly smaller
296			NavigableSet ns = subSet.subSet(first, false, last, false);
297	jsr166	1.2	// slight expansion
298	jsr166	1.6	assertThrowsIAE(() -> {
299	jsr166	1.1	ns.subSet(first, true, last, true);
300			},
301			description + ": Expansion should not be allowed");
302
303			// much smaller
304			subSet.subSet(first, false, BigInteger.ONE, false);
305			}
306
307			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
308			public void testheadSetRanges(String description, NavigableSet navigableSet) {
309			NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
310
311			// same subset
312			subSet.headSet(BigInteger.ONE, true);
313
314			// slightly smaller
315			NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
316
317	jsr166	1.2	// slight expansion
318	jsr166	1.6	assertThrowsIAE(() -> {
319	jsr166	1.1	ns.headSet(BigInteger.ONE, true);
320			},
321			description + ": Expansion should not be allowed");
322
323			// much smaller
324			subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
325			}
326
327			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
328			public void testTailSetRanges(String description, NavigableSet navigableSet) {
329			NavigableSet subSet = navigableSet.tailSet(BigInteger.ONE, true);
330
331			// same subset
332			subSet.tailSet(BigInteger.ONE, true);
333
334			// slightly smaller
335			NavigableSet ns = subSet.tailSet(BigInteger.ONE, false);
336
337	jsr166	1.2	// slight expansion
338	jsr166	1.6	assertThrowsIAE(() -> {
339	jsr166	1.1	ns.tailSet(BigInteger.ONE, true);
340			},
341			description + ": Expansion should not be allowed");
342
343			// much smaller
344			subSet.tailSet(isDescending(subSet) ? BigInteger.ZERO : BigInteger.TEN, false);
345			}
346
347			/**
348			* Tests the tailSet() method.
349			*/
350			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
351			public void testTailSet(String description, NavigableSet navigableSet) {
352	jsr166	1.6	assertThrowsNPE(() -> {
353	jsr166	1.1	navigableSet.tailSet(null);
354			},
355			description + ": Must throw NullPointerException for null element");
356
357	jsr166	1.6	assertThrowsCCE(() -> {
358	jsr166	1.1	navigableSet.tailSet(new Object());
359	jsr166	1.6	}, description);
360	jsr166	1.1
361			NavigableSet ss = navigableSet.tailSet("1", true);
362
363			assertEmptyNavigableSet(ss, description + ": Returned value is not empty navigable set.");
364			}
365
366			/**
367			* Tests that the array has a size of 0.
368			*/
369			@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
370			public void testToArray(String description, NavigableSet<?> navigableSet) {
371			Object[] emptyNavigableSetArray = navigableSet.toArray();
372
373			assertTrue(emptyNavigableSetArray.length == 0, "Returned non-empty Array.");
374
375			emptyNavigableSetArray = new Object[20];
376
377			Object[] result = navigableSet.toArray(emptyNavigableSetArray);
378
379			assertSame(emptyNavigableSetArray, result);
380
381			assertTrue(result[0] == null);
382			}
383
384			@DataProvider(name = "NavigableSet<?>", parallel = true)
385			public static Iterator<Object[]> navigableSetsProvider() {
386			return makeNavigableSets().iterator();
387			}
388
389			public static Collection<Object[]> makeNavigableSets() {
390			return Arrays.asList(
391			new Object[]{"UnmodifiableNavigableSet(TreeSet)", Collections.unmodifiableNavigableSet(new TreeSet())},
392			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet())},
393			new Object[]{"UnmodifiableNavigableSet(TreeSet.descendingSet().descendingSet()", Collections.unmodifiableNavigableSet(new TreeSet().descendingSet().descendingSet())},
394			new Object[]{"emptyNavigableSet()", Collections.emptyNavigableSet()},
395			new Object[]{"emptyNavigableSet().descendingSet()", Collections.emptyNavigableSet().descendingSet()},
396			new Object[]{"emptyNavigableSet().descendingSet().descendingSet()", Collections.emptyNavigableSet().descendingSet().descendingSet()}
397			);
398			}
399			}