1 /*
2 * Copyright (c) 2013, 2018, 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 /* @test
25 * @bug 8195649
26 * @summary Basic functional test of Optional
27 * @author Mike Duigou
28 * @build ObscureException
29 * @run testng Basic
30 */
31
32 import java.util.List;
33 import java.util.NoSuchElementException;
34 import java.util.Optional;
35 import java.util.concurrent.atomic.AtomicBoolean;
36 import java.util.function.Predicate;
37
38 import static java.util.stream.Collectors.toList;
39
40 import static org.testng.Assert.*;
41 import org.testng.annotations.Test;
42
43 public class Basic {
44
45 /**
46 * Checks a block of assertions over an empty Optional.
47 */
48 void checkEmpty(Optional<String> empty) {
49 assertTrue(empty.equals(Optional.empty()));
50 assertTrue(Optional.empty().equals(empty));
51 assertFalse(empty.equals(Optional.of("unexpected")));
52 assertFalse(Optional.of("unexpected").equals(empty));
53 assertFalse(empty.equals("unexpected"));
54
55 assertFalse(empty.isPresent());
56 assertTrue(empty.isEmpty());
57 assertEquals(empty.hashCode(), 0);
58 assertEquals(empty.orElse("x"), "x");
59 assertEquals(empty.orElseGet(() -> "y"), "y");
60
61 assertThrows(NoSuchElementException.class, () -> empty.get());
62 assertThrows(NoSuchElementException.class, () -> empty.orElseThrow());
63 assertThrows(ObscureException.class, () -> empty.orElseThrow(ObscureException::new));
64
65 var b = new AtomicBoolean();
66 empty.ifPresent(s -> b.set(true));
67 assertFalse(b.get());
68
69 var b1 = new AtomicBoolean(false);
70 var b2 = new AtomicBoolean(false);
71 empty.ifPresentOrElse(s -> b1.set(true), () -> b2.set(true));
72 assertFalse(b1.get());
73 assertTrue(b2.get());
74
75 assertEquals(empty.toString(), "Optional.empty");
76 }
77
78 /**
79 * Checks a block of assertions over an Optional that is expected to
80 * have a particular value present.
81 */
82 void checkPresent(Optional<String> opt, String expected) {
83 assertFalse(opt.equals(Optional.empty()));
84 assertFalse(Optional.empty().equals(opt));
85 assertTrue(opt.equals(Optional.of(expected)));
86 assertTrue(Optional.of(expected).equals(opt));
87 assertFalse(opt.equals(Optional.of("unexpected")));
88 assertFalse(Optional.of("unexpected").equals(opt));
89 assertFalse(opt.equals("unexpected"));
90
91 assertTrue(opt.isPresent());
92 assertEquals(opt.hashCode(), expected.hashCode());
93 assertEquals(opt.orElse("unexpected"), expected);
94 assertEquals(opt.orElseGet(() -> "unexpected"), expected);
95
96 assertEquals(opt.get(), expected);
97 assertEquals(opt.orElseThrow(), expected);
98 assertEquals(opt.orElseThrow(ObscureException::new), expected);
99
100 var b = new AtomicBoolean(false);
101 opt.ifPresent(s -> b.set(true));
102 assertTrue(b.get());
103
104 var b1 = new AtomicBoolean(false);
105 var b2 = new AtomicBoolean(false);
106 opt.ifPresentOrElse(s -> b1.set(true), () -> b2.set(true));
107 assertTrue(b1.get());
108 assertFalse(b2.get());
109
110 assertEquals(opt.toString(), "Optional[" + expected + "]");
111 }
112
113 @Test(groups = "unit")
114 public void testEmpty() {
115 checkEmpty(Optional.empty());
116 }
117
118 @Test(groups = "unit")
119 public void testOfNull() {
120 assertThrows(NullPointerException.class, () -> Optional.of(null));
121 }
122
123 @Test(groups = "unit")
124 public void testOfPresent() {
125 checkPresent(Optional.of("xyzzy"), "xyzzy");
126 }
127
128 @Test(groups = "unit")
129 public void testOfNullableNull() {
130 checkEmpty(Optional.ofNullable(null));
131 }
132
133 @Test(groups = "unit")
134 public void testOfNullablePresent() {
135 checkPresent(Optional.ofNullable("xyzzy"), "xyzzy");
136 }
137
138 @Test(groups = "unit")
139 public void testFilterEmpty() {
140 checkEmpty(Optional.<String>empty().filter(s -> { fail(); return true; }));
141 }
142
143 @Test(groups = "unit")
144 public void testFilterFalse() {
145 checkEmpty(Optional.of("xyzzy").filter(s -> s.equals("plugh")));
146 }
147
148 @Test(groups = "unit")
149 public void testFilterTrue() {
150 checkPresent(Optional.of("xyzzy").filter(s -> s.equals("xyzzy")), "xyzzy");
151 }
152
153 @Test(groups = "unit")
154 public void testMapEmpty() {
155 checkEmpty(Optional.empty().map(s -> { fail(); return ""; }));
156 }
157
158 @Test(groups = "unit")
159 public void testMapPresent() {
160 checkPresent(Optional.of("xyzzy").map(s -> s.replace("xyzzy", "plugh")), "plugh");
161 }
162
163 @Test(groups = "unit")
164 public void testFlatMapEmpty() {
165 checkEmpty(Optional.empty().flatMap(s -> { fail(); return Optional.of(""); }));
166 }
167
168 @Test(groups = "unit")
169 public void testFlatMapPresentReturnEmpty() {
170 checkEmpty(Optional.of("xyzzy")
171 .flatMap(s -> { assertEquals(s, "xyzzy"); return Optional.empty(); }));
172 }
173
174 @Test(groups = "unit")
175 public void testFlatMapPresentReturnPresent() {
176 checkPresent(Optional.of("xyzzy")
177 .flatMap(s -> { assertEquals(s, "xyzzy"); return Optional.of("plugh"); }),
178 "plugh");
179 }
180
181 @Test(groups = "unit")
182 public void testOrEmptyEmpty() {
183 checkEmpty(Optional.<String>empty().or(() -> Optional.empty()));
184 }
185
186 @Test(groups = "unit")
187 public void testOrEmptyPresent() {
188 checkPresent(Optional.<String>empty().or(() -> Optional.of("plugh")), "plugh");
189 }
190
191 @Test(groups = "unit")
192 public void testOrPresentDontCare() {
193 checkPresent(Optional.of("xyzzy").or(() -> { fail(); return Optional.of("plugh"); }), "xyzzy");
194 }
195
196 @Test(groups = "unit")
197 public void testStreamEmpty() {
198 assertEquals(Optional.empty().stream().collect(toList()), List.of());
199 }
200
201 @Test(groups = "unit")
202 public void testStreamPresent() {
203 assertEquals(Optional.of("xyzzy").stream().collect(toList()), List.of("xyzzy"));
204 }
205
206 @Test(groups = "unit")
207 public void testIsEmpty() {
208 var integerList = List.of(1,2,3,4,5);
209 Predicate<Integer> isPositiveNumber = x -> x > 0;
210 Predicate<Integer> isNegativeNumber = x -> x < 0;
211 Optional<Integer> positiveNumber = integerList.stream().filter(isPositiveNumber).findAny();
212 Optional<Integer> negativeNumber = integerList.stream().filter(isNegativeNumber).findAny();
213 assertFalse(positiveNumber.isEmpty());
214 assertTrue(negativeNumber.isEmpty());
215 }
216 }