test/tools/javac/generics/wildcards/pos/CastTest.java

Wed, 13 Aug 2014 14:50:00 -0700

author
katleman
date
Wed, 13 Aug 2014 14:50:00 -0700
changeset 2549
0b6cc4ea670f
parent 554
9d9f26857129
child 2525
2eb010b6cb22
permissions
-rw-r--r--

Added tag jdk8u40-b01 for changeset bf89a471779d

duke@1 1 /*
ohair@554 2 * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
duke@1 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1 4 *
duke@1 5 * This code is free software; you can redistribute it and/or modify it
duke@1 6 * under the terms of the GNU General Public License version 2 only, as
duke@1 7 * published by the Free Software Foundation.
duke@1 8 *
duke@1 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@1 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@1 13 * accompanied this code).
duke@1 14 *
duke@1 15 * You should have received a copy of the GNU General Public License version
duke@1 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@1 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1 18 *
ohair@554 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554 20 * or visit www.oracle.com if you need additional information or have any
ohair@554 21 * questions.
duke@1 22 */
duke@1 23
duke@1 24 /*
duke@1 25 * @test
duke@1 26 * @bug 4916607
duke@1 27 * @summary Test casts (legal, warning, and errors)
duke@1 28 * @author gafter
duke@1 29 *
darcy@289 30 * @compile -Werror CastTest.java
duke@1 31 */
duke@1 32
duke@1 33 import java.util.*;
duke@1 34
duke@1 35 class CastTest {
duke@1 36
duke@1 37 // --- Directly transferring parameters ---
duke@1 38
duke@1 39 private class AA<T> { }
duke@1 40
duke@1 41 private class AB<T> extends AA<T> { }
duke@1 42 private class AC<T> extends AA<Vector<T>> { }
duke@1 43 private class AD<T> extends AA<Vector<? extends T>> { }
duke@1 44 private class AE<T> extends AA<Vector<? super T>> { }
duke@1 45 private class AF<T> extends AA<T[]> { }
duke@1 46 private class AG<T> extends AA<String> { }
duke@1 47
duke@1 48 private void parameterTransfer() {
duke@1 49 Object o;
duke@1 50
duke@1 51 o = (AB<String>) (AA<String>) null; // <<pass>>
duke@1 52 o = (AC<String>) (AA<Vector<String>>) null; // <<pass>>
duke@1 53
duke@1 54 o = (AD<Number>) (AA<Vector<? extends Number>>) null; // <<pass>>
duke@1 55 o = (AD<?>) (AA<Vector<? extends Object>>) null; // <<pass>>
duke@1 56 o = (AD<Object>) (AA<Vector<?>>) null; // <<pass>>
duke@1 57
duke@1 58 o = (AE<String>) (AA<Vector<? super String>>) null; // <<pass>>
duke@1 59
duke@1 60 o = (AF<String>) (AA<String[]>) null; // <<pass>>
duke@1 61
duke@1 62 o = (AG<?>) (AA<String>) null; // <<pass>>
duke@1 63 }
duke@1 64
duke@1 65 // --- Inconsistent matches ---
duke@1 66
duke@1 67 private class BA<T> { }
duke@1 68 private class BB<T, S> { }
duke@1 69
duke@1 70 private class BC<T> extends BA<Integer> { }
duke@1 71 private class BD<T> extends BB<T, T> { }
duke@1 72
duke@1 73 private void inconsistentMatches() {
duke@1 74 Object o;
duke@1 75
duke@1 76 o = (BC<?>) (BA<Integer>) null; // <<pass>>
duke@1 77 o = (BD<String>) (BB<String, String>) null; // <<pass>>
duke@1 78 }
duke@1 79
duke@1 80 private void whyMustEverythingBeSo_______Complicated() {
duke@1 81 // This has to work...
duke@1 82 BD<Number> bd = new BD<Number>();
duke@1 83 BB<? extends Number, ? super Integer> bb = bd;
duke@1 84
duke@1 85 // 4916620: wildcards: legal cast is rejected
duke@1 86 // bd = (BD<Number>) bb; // <<warn>> <<todo: cast-infer>>
duke@1 87 }
duke@1 88
duke@1 89 // --- Transferring parameters via supertypes ---
duke@1 90
duke@1 91 private interface CA<T> { }
duke@1 92 private interface CB<T> extends CA<T> { }
duke@1 93 private interface CC<T> extends CA<T> { }
duke@1 94
duke@1 95 private class CD<T> implements CB<T> { }
duke@1 96 private interface CE<T> extends CC<T> { }
duke@1 97
duke@1 98 private interface CF<S> { }
duke@1 99 private interface CG<T> { }
duke@1 100 private class CH<S, T> implements CF<S>, CG<T> { }
duke@1 101 private interface CI<S> extends CF<S> { }
duke@1 102 private interface CJ<T> extends CG<T> { }
duke@1 103 private interface CK<S, T> extends CI<S>, CJ<T> { }
duke@1 104
duke@1 105 private void supertypeParameterTransfer() {
duke@1 106 Object o;
duke@1 107 o = (CE<String>) (CD<String>) null; // <<pass>>
duke@1 108
duke@1 109 // 4916622: unnecessary warning with cast
duke@1 110 // o = (CH<String, Integer>) (CK<String, Integer>) null; // <<pass>> <<todo: cast-infer>>
duke@1 111 }
duke@1 112
duke@1 113 // --- Disjoint ---
duke@1 114
duke@1 115 private interface DA<T> { }
duke@1 116 private interface DB<T> extends DA<T> { }
duke@1 117 private interface DC<T> extends DA<Integer> { }
duke@1 118
duke@1 119 private <N extends Number, I extends Integer, R extends Runnable, S extends String> void disjointness() {
duke@1 120 Object o;
duke@1 121
duke@1 122 // Classes
duke@1 123 o = (DA<? extends Number>) (DA<Integer>) null; // <<pass>>
duke@1 124 o = (DA<? super Integer>) (DA<Number>) null; // <<pass>>
duke@1 125 o = (DA<?>) (DA<Integer>) null; // <<pass>>
duke@1 126
duke@1 127 o = (DA<?>) (DA<? extends Integer>) null; // <<pass>>
duke@1 128
duke@1 129 o = (DA<?>) (DA<? super String>) null; // <<pass>>
duke@1 130
duke@1 131 o = (DA<?>) (DA<?>) null; // <<pass>>
duke@1 132
duke@1 133 // Typevars
duke@1 134 o = (DA<? extends Number>) (DA<I>) null; // <<pass>>
duke@1 135
duke@1 136 // Raw (asymmetrical!)
duke@1 137 o = (DA) (DB<Number>) null; // <<pass>>
duke@1 138 o = (DA<?>) (DB) null; // <<pass>>
duke@1 139 o = (DA<? extends Object>) (DB) null; // <<pass>>
duke@1 140
duke@1 141 o = (DB) (DA<Number>) null; // <<pass>>
duke@1 142 o = (DB<?>) (DA) null; // <<pass>>
duke@1 143 o = (DB<? extends Object>) (DA) null; // <<pass>>
duke@1 144
duke@1 145 // reported broken (5034609)
duke@1 146 // o = (DC<?>) (DA<?>) null; // <<pass>>
duke@1 147 }
duke@1 148
duke@1 149 }

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