Java example source code file (Covar2.java)

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Java - Java tags/keywords

covar2, long

The Covar2.java Java example source code

/*
 * Copyright (c) 2003, 2004, 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 4949303 4960369 4965756
 * @summary Additional unit tests for covariant returns
 * @author gafter
 *
 * @compile  Covar2.java
 * @run main Covar2
 */

public class Covar2 {
    static class A1 {
        public Long f() { return 12L; }
    }
    static class B1 extends A1 {
        public Long f() { return 12L; }
    }

    static class B2 {
        public int f() { return 12; }
    }
    static class C2 extends B2 {
        public int f() { return (short)12; }
    }

    static class C3 extends B2 {
        public int f() { return (short)12; }
    }

    public static void main(String[] args) {
        A1 b1 = new B1();
        System.out.println(b1.f());

        B2 c2 = new C2();
        System.out.println(c2.f());

        B2 c3 = new C3();
        System.out.println(c3.f());
    }
}