Java example source code file (LambdaConv20.java)

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Java - Java tags/keywords

assertionerror, lambdaconv20, sam, util

The LambdaConv20.java Java example source code

/*
 * Copyright (c) 2011, 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 8003280
 * @summary Add lambda tests
 *  check that synthetic casts are added when erased type of lambda body
 *          ends up being too general
 * @run main LambdaConv20
 */

import java.util.*;

public class LambdaConv20 {

    static int assertionCount = 0;

    static void assertTrue(boolean cond) {
        assertionCount++;
        if (!cond)
            throw new AssertionError();
    }

    interface SAM<X> {
        X m(List<X> l);
    }

    public static void main(String[] args) {
        SAM<Integer> si1 = l -> l.get(0);
        assertTrue(si1.m(Arrays.asList(1)) == 1);
        SAM<Integer> si2 = l -> { return l.get(0); };
        assertTrue(si2.m(Arrays.asList(1)) == 1);
        assertTrue(assertionCount == 2);
    }
}