Java example source code file (PotentiallyAmbiguousWarningTest.java)

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The PotentiallyAmbiguousWarningTest.java Java example source code

/*
 * Copyright (c) 2013, 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 8024947
 * @summary javac should issue the potentially ambiguous overload warning only
 * where the problem appears
 * @compile/fail/ref=PotentiallyAmbiguousWarningTest.out -XDrawDiagnostics -Werror -Xlint:overloads PotentiallyAmbiguousWarningTest.java
 * @compile PotentiallyAmbiguousWarningTest.java
 */

import java.util.function.*;

public interface PotentiallyAmbiguousWarningTest {

    //a warning should be fired
    interface I1 {
        void foo(Consumer<Integer> c);
        void foo(IntConsumer c);
    }

    //a warning should be fired
    class C1 {
        void foo(Consumer<Integer> c) { }
        void foo(IntConsumer c) { }
    }

    interface I2 {
        void foo(Consumer<Integer> c);
    }

    //a warning should be fired, J1 is provoking the issue
    interface J1 extends I2 {
        void foo(IntConsumer c);
    }

    //no warning here, the issue is introduced in I1
    interface I3 extends I1 {}

    //no warning here, the issue is introduced in I1. I4 is just overriding an existing method
    interface I4 extends I1 {
        void foo(IntConsumer c);
    }

    class C2 {
        void foo(Consumer<Integer> c) { }
    }

    //a warning should be fired, D1 is provoking the issue
    class D1 extends C2 {
        void foo(IntConsumer c) { }
    }

    //a warning should be fired, C3 is provoking the issue
    class C3 implements I2 {
        public void foo(Consumer<Integer> c) { }
        public void foo(IntConsumer c) { }
    }

    //no warning here, the issue is introduced in C1
    class C4 extends C1 {}

    //no warning here, the issue is introduced in C1. C5 is just overriding an existing method
    class C5 extends C1 {
        void foo(IntConsumer c) {}
    }

    interface I5<T> {
        void foo(T c);
    }

    //a warning should be fired, J2 is provoking the issue
    interface J2 extends I5<IntConsumer> {
        void foo(Consumer<Integer> c);
    }
}