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/*
* Copyright (c) 2003, 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 4916607
* @summary Test casts (legal, warning, and errors)
* @author gafter
*
* @compile/fail -Werror -Xlint:unchecked CastWarn14.java
*/
import java.util.*;
class CastTest {
// --- Directly transferring parameters ---
private class AA<T> { }
private class AB<T> extends AA<T> { }
private class AC<T> extends AA<Vector<T>> { }
private class AD<T> extends AA<Vector<? extends T>> { }
private class AE<T> extends AA<Vector<? super T>> { }
private class AF<T> extends AA<T[]> { }
private class AG<T> extends AA<String> { }
private void parameterTransfer() {
Object o;
o = (AB<String>) (AA<String>) null; // <<pass>>
o = (AB<String>) (AA<Number>) null; // <<fail 1>>
o = (AC<String>) (AA<Vector<String>>) null; // <<pass>>
o = (AC<String>) (AA<Vector<Number>>) null; // <<fail 2>>
o = (AC<String>) (AA<Stack<String>>) null; // <<fail 3>>
o = (AD<Number>) (AA<Vector<? extends Number>>) null; // <<pass>>
o = (AD<String>) (AA<Vector<? extends Number>>) null; // <<fail 4>>
o = (AD<?>) (AA<Vector<? extends Object>>) null; // <<pass>>
o = (AD<Object>) (AA<Vector<?>>) null; // <<pass>>
o = (AE<String>) (AA<Vector<? super String>>) null; // <<pass>>
o = (AE<Number>) (AA<Vector<? super String>>) null; // <<fail 5>>
o = (AF<String>) (AA<String[]>) null; // <<pass>>
o = (AF<String>) (AA<Number[]>) null; // <<fail 6>>
o = (AG<?>) (AA<String>) null; // <<pass>>
o = (AG<?>) (AA<Number>) null; // <<fail 7>>
}
// --- Inconsistent matches ---
private class BA<T> { }
private class BB<T, S> { }
private class BC<T> extends BA<Integer> { }
private class BD<T> extends BB<T, T> { }
private void inconsistentMatches() {
Object o;
o = (BC<?>) (BA<Integer>) null; // <<pass>>
o = (BC<?>) (BA<String>) null; // <<fail 8>>
o = (BD<String>) (BB<String, String>) null; // <<pass>>
o = (BD<String>) (BB<String, Number>) null; // <<fail 9>>
o = (BD<String>) (BB<Number, String>) null; // <<fail 10>>
}
private void whyMustEverythingBeSo_______Complicated() {
// This has to work...
BD<Number> bd = new BD<Number>();
BB<? extends Number, ? super Integer> bb = bd;
// 4916620: wildcards: legal cast is rejected
// bd = (BD<Number>) bb; // <<warn>> <<todo: cast-infer>>
}
// --- Transferring parameters via supertypes ---
private interface CA<T> { }
private interface CB<T> extends CA<T> { }
private interface CC<T> extends CA<T> { }
private class CD<T> implements CB<T> { }
private interface CE<T> extends CC<T> { }
private interface CF<S> { }
private interface CG<T> { }
private class CH<S, T> implements CF<S>, CG<T> { }
private interface CI<S> extends CF<S> { }
private interface CJ<T> extends CG<T> { }
private interface CK<S, T> extends CI<S>, CJ<T> { }
private void supertypeParameterTransfer() {
Object o;
CD<?> cd = (CE<?>) null; // <<fail 11>>
CE<?> ce = (CD<?>) null; // <<fail 12>>
o = (CE<String>) (CD<String>) null; // <<pass>>
o = (CE<Number>) (CD<String>) null; // <<fail 13>>
// 4916622: unnecessary warning with cast
// o = (CH<String, Integer>) (CK<String, Integer>) null; // <<pass>> <<todo: cast-infer>>
}
// --- Disjoint ---
private interface DA<T> { }
private interface DB<T> extends DA<T> { }
private interface DC<T> extends DA<Integer> { }
private <N extends Number, I extends Integer, R extends Runnable, S extends String> void disjointness() {
Object o;
// Classes
o = (DA<Number>) (DA<Integer>) null; // <<fail 14>>
o = (DA<? extends Number>) (DA<Integer>) null; // <<pass>>
o = (DA<? extends Integer>) (DA<Number>) null; // <<fail 15>>
o = (DA<? super Integer>) (DA<Number>) null; // <<pass>>
o = (DA<? super Number>) (DA<Integer>) null; // <<fail 16>>
o = (DA<?>) (DA<Integer>) null; // <<pass>>
o = (DA<? extends Runnable>) (DA<? extends Number>) null; // <<warn 2>>
o = (DA<? extends Runnable>) (DA<? extends String>) null; // <<fail 17>>
o = (DA<? super Integer>) (DA<? extends Number>) null; // <<warn 3>>
o = (DA<? super Number>) (DA<? extends Integer>) null; // <<fail 18>>
o = (DA<?>) (DA<? extends Integer>) null; // <<pass>>
o = (DA<? super String>) (DA<? super Number>) null; // <<warn 4>>
o = (DA<?>) (DA<? super String>) null; // <<pass>>
o = (DA<?>) (DA<?>) null; // <<pass>>
// Typevars
o = (DA<? extends Number>) (DA<I>) null; // <<pass>>
o = (DA<? extends Integer>) (DA<N>) null; // <<warn 5>>
o = (DA<? extends String>) (DA<I>) null; // <<fail 19>>
o = (DA<I>) (DA<? extends Number>) null; // <<warn 6>>
o = (DA<N>) (DA<? extends Integer>) null; // <<warn 7>>
o = (DA<N>) (DA<? extends Runnable>) null; // <<warn 8>>
o = (DA<N>) (DA<I>) null; // <<warn 9>>
o = (DA<N>) (DA<R>) null; // <<warn 10>>
o = (DA<S>) (DA<R>) null; // <<fail 20>>
// Raw (asymmetrical!)
o = (DA) (DB<Number>) null; // <<pass>>
o = (DA<Number>) (DB) null; // <<warn 11>>
o = (DA<?>) (DB) null; // <<pass>>
o = (DA<? extends Object>) (DB) null; // <<pass>>
o = (DA<? extends Number>) (DB) null; // <<warn 12>>
o = (DB) (DA<Number>) null; // <<pass>>
o = (DB<Number>) (DA) null; // <<warn 13>>
o = (DB<?>) (DA) null; // <<pass>>
o = (DB<? extends Object>) (DA) null; // <<pass>>
o = (DB<? extends Number>) (DA) null; // <<warn 14>>
o = (DC<?>) (DA<?>) null; // <<pass>>
o = (DC<?>) (DA<? super String>) null; // <<fail 21>>
}
}
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