Sat, 01 Dec 2007 00:00:00 +0000
Initial load
1 /*
2 * Copyright 2003-2004 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 */
24 /*
25 * @test
26 * @bug 4916607
27 * @summary Test casts (legal, warning, and errors)
28 * @author gafter
29 *
30 * @compile -source 1.5 -Werror CastTest.java
31 */
33 import java.util.*;
35 class CastTest {
37 // --- Directly transferring parameters ---
39 private class AA<T> { }
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> { }
48 private void parameterTransfer() {
49 Object o;
51 o = (AB<String>) (AA<String>) null; // <<pass>>
52 o = (AC<String>) (AA<Vector<String>>) null; // <<pass>>
54 o = (AD<Number>) (AA<Vector<? extends Number>>) null; // <<pass>>
55 o = (AD<?>) (AA<Vector<? extends Object>>) null; // <<pass>>
56 o = (AD<Object>) (AA<Vector<?>>) null; // <<pass>>
58 o = (AE<String>) (AA<Vector<? super String>>) null; // <<pass>>
60 o = (AF<String>) (AA<String[]>) null; // <<pass>>
62 o = (AG<?>) (AA<String>) null; // <<pass>>
63 }
65 // --- Inconsistent matches ---
67 private class BA<T> { }
68 private class BB<T, S> { }
70 private class BC<T> extends BA<Integer> { }
71 private class BD<T> extends BB<T, T> { }
73 private void inconsistentMatches() {
74 Object o;
76 o = (BC<?>) (BA<Integer>) null; // <<pass>>
77 o = (BD<String>) (BB<String, String>) null; // <<pass>>
78 }
80 private void whyMustEverythingBeSo_______Complicated() {
81 // This has to work...
82 BD<Number> bd = new BD<Number>();
83 BB<? extends Number, ? super Integer> bb = bd;
85 // 4916620: wildcards: legal cast is rejected
86 // bd = (BD<Number>) bb; // <<warn>> <<todo: cast-infer>>
87 }
89 // --- Transferring parameters via supertypes ---
91 private interface CA<T> { }
92 private interface CB<T> extends CA<T> { }
93 private interface CC<T> extends CA<T> { }
95 private class CD<T> implements CB<T> { }
96 private interface CE<T> extends CC<T> { }
98 private interface CF<S> { }
99 private interface CG<T> { }
100 private class CH<S, T> implements CF<S>, CG<T> { }
101 private interface CI<S> extends CF<S> { }
102 private interface CJ<T> extends CG<T> { }
103 private interface CK<S, T> extends CI<S>, CJ<T> { }
105 private void supertypeParameterTransfer() {
106 Object o;
107 o = (CE<String>) (CD<String>) null; // <<pass>>
109 // 4916622: unnecessary warning with cast
110 // o = (CH<String, Integer>) (CK<String, Integer>) null; // <<pass>> <<todo: cast-infer>>
111 }
113 // --- Disjoint ---
115 private interface DA<T> { }
116 private interface DB<T> extends DA<T> { }
117 private interface DC<T> extends DA<Integer> { }
119 private <N extends Number, I extends Integer, R extends Runnable, S extends String> void disjointness() {
120 Object o;
122 // Classes
123 o = (DA<? extends Number>) (DA<Integer>) null; // <<pass>>
124 o = (DA<? super Integer>) (DA<Number>) null; // <<pass>>
125 o = (DA<?>) (DA<Integer>) null; // <<pass>>
127 o = (DA<?>) (DA<? extends Integer>) null; // <<pass>>
129 o = (DA<?>) (DA<? super String>) null; // <<pass>>
131 o = (DA<?>) (DA<?>) null; // <<pass>>
133 // Typevars
134 o = (DA<? extends Number>) (DA<I>) null; // <<pass>>
136 // Raw (asymmetrical!)
137 o = (DA) (DB<Number>) null; // <<pass>>
138 o = (DA<?>) (DB) null; // <<pass>>
139 o = (DA<? extends Object>) (DB) null; // <<pass>>
141 o = (DB) (DA<Number>) null; // <<pass>>
142 o = (DB<?>) (DA) null; // <<pass>>
143 o = (DB<? extends Object>) (DA) null; // <<pass>>
145 // reported broken (5034609)
146 // o = (DC<?>) (DA<?>) null; // <<pass>>
147 }
149 }