1 /*
2 * Copyright 2003 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 */
23
24 /*
25 * @test
26 * @bug 4916607
27 * @summary Test casts (legal, warning, and errors)
28 * @author gafter
29 *
30 * @compile/fail -source 1.5 -Werror -Xlint:unchecked CastWarn14.java
31 */
32
33 import java.util.*;
34
35 class CastTest {
36
37 // --- Directly transferring parameters ---
38
39 private class AA<T> { }
40
41 private class AB<T> extends AA<T> { }
42 private class AC<T> extends AA<Vector<T>> { }
43 private class AD<T> extends AA<Vector<? extends T>> { }
44 private class AE<T> extends AA<Vector<? super T>> { }
45 private class AF<T> extends AA<T[]> { }
46 private class AG<T> extends AA<String> { }
47
48 private void parameterTransfer() {
49 Object o;
50
51 o = (AB<String>) (AA<String>) null; // <<pass>>
52 o = (AB<String>) (AA<Number>) null; // <<fail 1>>
53 o = (AC<String>) (AA<Vector<String>>) null; // <<pass>>
54 o = (AC<String>) (AA<Vector<Number>>) null; // <<fail 2>>
55 o = (AC<String>) (AA<Stack<String>>) null; // <<fail 3>>
56
57 o = (AD<Number>) (AA<Vector<? extends Number>>) null; // <<pass>>
58 o = (AD<String>) (AA<Vector<? extends Number>>) null; // <<fail 4>>
59 o = (AD<?>) (AA<Vector<? extends Object>>) null; // <<pass>>
60 o = (AD<Object>) (AA<Vector<?>>) null; // <<pass>>
61
62 o = (AE<String>) (AA<Vector<? super String>>) null; // <<pass>>
63 o = (AE<Number>) (AA<Vector<? super String>>) null; // <<fail 5>>
64
65 o = (AF<String>) (AA<String[]>) null; // <<pass>>
66 o = (AF<String>) (AA<Number[]>) null; // <<fail 6>>
67
68 o = (AG<?>) (AA<String>) null; // <<pass>>
69 o = (AG<?>) (AA<Number>) null; // <<fail 7>>
70 }
71
72 // --- Inconsistent matches ---
73
74 private class BA<T> { }
75 private class BB<T, S> { }
76
77 private class BC<T> extends BA<Integer> { }
78 private class BD<T> extends BB<T, T> { }
79
80 private void inconsistentMatches() {
81 Object o;
82
83 o = (BC<?>) (BA<Integer>) null; // <<pass>>
84 o = (BC<?>) (BA<String>) null; // <<fail 8>>
85 o = (BD<String>) (BB<String, String>) null; // <<pass>>
86 o = (BD<String>) (BB<String, Number>) null; // <<fail 9>>
87 o = (BD<String>) (BB<Number, String>) null; // <<fail 10>>
88 }
89
90 private void whyMustEverythingBeSo_______Complicated() {
91 // This has to work...
92 BD<Number> bd = new BD<Number>();
93 BB<? extends Number, ? super Integer> bb = bd;
94 // 4916620: wildcards: legal cast is rejected
95 // bd = (BD<Number>) bb; // <<warn>> <<todo: cast-infer>>
96 }
97
98 // --- Transferring parameters via supertypes ---
99
100 private interface CA<T> { }
101 private interface CB<T> extends CA<T> { }
102 private interface CC<T> extends CA<T> { }
103
104 private class CD<T> implements CB<T> { }
105 private interface CE<T> extends CC<T> { }
106
107 private interface CF<S> { }
108 private interface CG<T> { }
109 private class CH<S, T> implements CF<S>, CG<T> { }
110 private interface CI<S> extends CF<S> { }
111 private interface CJ<T> extends CG<T> { }
112 private interface CK<S, T> extends CI<S>, CJ<T> { }
113
114 private void supertypeParameterTransfer() {
115 Object o;
116 CD<?> cd = (CE<?>) null; // <<fail 11>>
117 CE<?> ce = (CD<?>) null; // <<fail 12>>
118 o = (CE<String>) (CD<String>) null; // <<pass>>
119 o = (CE<Number>) (CD<String>) null; // <<fail 13>>
120
121 // 4916622: unnecessary warning with cast
122 // o = (CH<String, Integer>) (CK<String, Integer>) null; // <<pass>> <<todo: cast-infer>>
123 }
124
125 // --- Disjoint ---
126
127 private interface DA<T> { }
128 private interface DB<T> extends DA<T> { }
129 private interface DC<T> extends DA<Integer> { }
130
131 private <N extends Number, I extends Integer, R extends Runnable, S extends String> void disjointness() {
132 Object o;
133
134 // Classes
135 o = (DA<Number>) (DA<Integer>) null; // <<fail 14>>
136 o = (DA<? extends Number>) (DA<Integer>) null; // <<pass>>
137 o = (DA<? extends Integer>) (DA<Number>) null; // <<fail 15>>
138 o = (DA<? super Integer>) (DA<Number>) null; // <<pass>>
139 o = (DA<? super Number>) (DA<Integer>) null; // <<fail 16>>
140 o = (DA<?>) (DA<Integer>) null; // <<pass>>
141
142 o = (DA<? extends Runnable>) (DA<? extends Number>) null; // <<warn 2>>
143 o = (DA<? extends Runnable>) (DA<? extends String>) null; // <<fail 17>>
144
145 o = (DA<? super Integer>) (DA<? extends Number>) null; // <<warn 3>>
146 o = (DA<? super Number>) (DA<? extends Integer>) null; // <<fail 18>>
147 o = (DA<?>) (DA<? extends Integer>) null; // <<pass>>
148
149 o = (DA<? super String>) (DA<? super Number>) null; // <<warn 4>>
150 o = (DA<?>) (DA<? super String>) null; // <<pass>>
151
152 o = (DA<?>) (DA<?>) null; // <<pass>>
153
154 // Typevars
155 o = (DA<? extends Number>) (DA<I>) null; // <<pass>>
156 o = (DA<? extends Integer>) (DA<N>) null; // <<warn 5>>
157 o = (DA<? extends String>) (DA<I>) null; // <<fail 19>>
158
159 o = (DA<I>) (DA<? extends Number>) null; // <<warn 6>>
160 o = (DA<N>) (DA<? extends Integer>) null; // <<warn 7>>
161 o = (DA<N>) (DA<? extends Runnable>) null; // <<warn 8>>
162
163 o = (DA<N>) (DA<I>) null; // <<warn 9>>
164 o = (DA<N>) (DA<R>) null; // <<warn 10>>
165 o = (DA<S>) (DA<R>) null; // <<fail 20>>
166
167 // Raw (asymmetrical!)
168 o = (DA) (DB<Number>) null; // <<pass>>
169 o = (DA<Number>) (DB) null; // <<warn 11>>
170 o = (DA<?>) (DB) null; // <<pass>>
171 o = (DA<? extends Object>) (DB) null; // <<pass>>
172 o = (DA<? extends Number>) (DB) null; // <<warn 12>>
173
174 o = (DB) (DA<Number>) null; // <<pass>>
175 o = (DB<Number>) (DA) null; // <<warn 13>>
176 o = (DB<?>) (DA) null; // <<pass>>
177 o = (DB<? extends Object>) (DA) null; // <<pass>>
178 o = (DB<? extends Number>) (DA) null; // <<warn 14>>
179
180 o = (DC<?>) (DA<?>) null; // <<pass>>
181 o = (DC<?>) (DA<? super String>) null; // <<fail 21>>
182 }
183
184 }