1 /*

     2  * Copyright (c) 2018, Google and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 package MyPackage;

    25 

    26 import java.util.List;

    27 

    28 /**

    29  * @test

    30  * @build Frame HeapMonitor

    31  * @summary Verifies the default GC with the Heap Monitor event system.

    32  * @compile HeapMonitorGCTest.java

    33  * @requires vm.gc == "G1" | vm.gc == "null"

    34  * @run main/othervm/native -agentlib:HeapMonitorTest MyPackage.HeapMonitorGCTest

    35  */

    36 

    37 /**

    38  * This test is checking that various GCs work as intended: events are sent, forcing GC works, etc.

    39  */

    40 public class HeapMonitorGCTest {

    41   public static void main(String[] args) {

    42     if (!HeapMonitor.eventStorageIsEmpty()) {

    43       throw new RuntimeException("Statistics should be null to begin with.");

    44     }

    45 

    46     HeapMonitor.enableSamplingEvents();

    47 

    48     List<Frame> frameList = HeapMonitor.allocate();

    49     frameList.add(new Frame("main", "([Ljava/lang/String;)V", "HeapMonitorGCTest.java", 48));

    50     Frame[] frames = frameList.toArray(new Frame[0]);

    51 

    52     if (!HeapMonitor.obtainedEvents(frames)) {

    53       throw new RuntimeException("No expected events were found.");

    54     }

    55 

    56     HeapMonitor.forceGarbageCollection();

    57 

    58     if (!HeapMonitor.garbageContains(frames)) {

    59       throw new RuntimeException("Forcing GC did not work, not a single object was collected.");

    60     }

    61   }

    62 }