Java example source code file (T4711570.java)

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t4711570

The T4711570.java Java example source code

/*
 * Copyright (c) 2002, 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 4711570
 * @summary generics: problem with methods when type parameter doesn't appear in signature
 * @author gafter
 *
 * @compile  T4711570.java
 */

class T4711570 {
    public static int fi() {
        return fi();
    }

    public static void gi() {
        fi();
        gi();
    }

    public static <T> int f() {
        return f();
    }

    public static <T> void g() {
        f();    // incompatible.types  found: <T>int required: java.lang.Object
        int i = f(); // workaround for f()
        g();    // incompatible.types  found: <T>void required: java.lang.Object
    }
    // required type looks strange

    public static <T> void h() {
        g();    // incompatible.types  found: <T>void required: java.lang.Object
    }

    public static <T> int f(T x) {
        return f(x);
    }

    public static <T> void g(T x) {
        f(x);
        g(x);   // incompatible.types  found: <T>void required: java.lang.Object
    }

    public static <T> void h(T x) {
        g(x);   // works fine now; why not in void g(T x)?
    }
}