/*

 * Copyright (c) 2016, 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 TestNumWorkerOutput

 * @bug 8165292

 * @summary Check that when PrintGCDetails is enabled, gc,task output is printed only once per collection.

 * @key gc

 * @requires vm.gc=="null"

 * @modules java.base/jdk.internal.misc

 * @library /test/lib

 * @build sun.hotspot.WhiteBox

 * @run main ClassFileInstaller sun.hotspot.WhiteBox

 * @run main/othervm -XX:+UseConcMarkSweepGC TestNumWorkerOutput UseConcMarkSweepGC

 * @run main/othervm -XX:+UseG1GC TestNumWorkerOutput UseG1GC

 */

import sun.hotspot.WhiteBox;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import jdk.test.lib.Platform;

import jdk.test.lib.process.OutputAnalyzer;

import jdk.test.lib.process.ProcessTools;

import static jdk.test.lib.Asserts.*;

public class TestNumWorkerOutput {

    public static void checkPatternOnce(String pattern, String what) throws Exception {

        Pattern r = Pattern.compile(pattern);

        Matcher m = r.matcher(what);

        if (!m.find()) {

            throw new RuntimeException("Could not find pattern " + pattern + " in output");

        }

        if (m.find()) {

            throw new RuntimeException("Could find pattern " + pattern + " in output more than once");

        }

    }

    public static void runTest(String gcArg) throws Exception {

        final String[] arguments = {

            "-Xbootclasspath/a:.",

            "-XX:+UnlockExperimentalVMOptions",

            "-XX:+UnlockDiagnosticVMOptions",

            "-XX:+WhiteBoxAPI",

            "-XX:+" + gcArg,

            "-Xmx10M",

            "-XX:+PrintGCDetails",

            GCTest.class.getName()

            };

        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(arguments);

        OutputAnalyzer output = new OutputAnalyzer(pb.start());

        output.shouldHaveExitValue(0);

        System.out.println(output.getStdout());

        String stdout = output.getStdout();

        checkPatternOnce(".*[info.*].*[gc,task.*].*GC\\(0\\) .*Using \\d+ workers of \\d+ for evacuation.*", stdout);

    }

    public static void main(String[] args) throws Exception {

        runTest(args[0]);

    }

    static class GCTest {

        private static final WhiteBox WB = WhiteBox.getWhiteBox();

        public static Object holder;

        public static void main(String [] args) {

            holder = new byte[100];

            WB.youngGC();

            System.out.println(holder);

        }

    }

}