Java example source code file (BadTest2.java)

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Java - Java tags/keywords

a\=i, badtest2, main

The BadTest2.java Java example source code

/*
 * Copyright (c) 2002, 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
 * @summary Regression test from odersky
 * @author odersky
 *
 * @compile  BadTest2.java
 */

// this used to be a negative regression test, but when we
// added variance it started passing, undoubtedly due to
// bug fixes.  The code looks OK.
class BadTest2 {

    interface I {}
    interface J {}
    static class C implements I, J {}
    static class D implements I, J {}

    static class Main {

        static C c = new C();
        static D d = new D();

        static <A> boolean equals(A x, A y) { return x.equals(y); }

        public static void main(String[] args) {
            equals(c, d); // infer A=I&J
        }
    }

}