TestInnerCtorRef.java

/*
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 * 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.
 *
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 */

import org.testng.annotations.Test;

import java.util.function.Supplier;

/**
 * TestInnerCtorRef
 */
// @Test
public class TestInnerCtorRef {

    public void testCtorRef() {
        A<String> a = A.make(() -> "");
    }
}

abstract class A<T> {
    abstract T make();

    private A() {
    }

    public interface Foo<T> { }
    public static<T> A<T> make(Supplier<T> factory) {
        class Local implements Foo<T> {
            Supplier<T> f = factory;
        }
        return new Helper<T>(Local::new);
    }

    private static class Helper<T> extends A<T> {

        private Helper(Supplier<Foo<T>> factory) {
        }

        @Override
        T make() {
            return null;
        }
    }
}