Java example source code file (LambdaTest3.java)

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Java - Java tags/keywords

assertionerror, lambdatest3, runnable

The LambdaTest3.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
 *   Test capture of "effectively final" local variable in lambda expressions
 * @compile LambdaTest3.java
 * @run main LambdaTest3
 */

public class LambdaTest3 {

    private static int count = 0;

    private static void assertTrue(boolean b) {
        if(!b)
            throw new AssertionError();
    }

    public static void main(String[] args) {
        final int N = 100;
        int n = 2; //effectively final variable

        Runnable r = ((Runnable)
            () -> {
                count += N;
                count += n;
            }
        );
        assertTrue(count == 0);
        r.run();
        assertTrue(count == 102);
    }
}