1 /*

     2  * Copyright (c) 2017, Oracle 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 gc.concurrent_phase_control;

    25 

    26 /*

    27  * Utility class that provides verification of expected behavior of

    28  * the Concurrent GC Phase Control WB API when the current GC supports

    29  * phase control.  The invoking test must provide WhiteBox access.

    30  */

    31 

    32 import sun.hotspot.WhiteBox;

    33 import java.util.Arrays;

    34 import java.util.HashSet;

    35 import java.util.List;

    36 import java.util.Set;

    37 

    38 public class CheckSupported {

    39 

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

    41 

    42     private static Set<String> toSet(List<String> list, String which)

    43         throws Exception

    44     {

    45         Set<String> result = new HashSet<String>(list);

    46         if (result.size() < list.size()) {

    47             throw new RuntimeException(which + " phases contains duplicates");

    48         }

    49         return result;

    50     }

    51 

    52     private static void checkPhases(String[] expectedPhases) throws Exception {

    53         String[] actualPhases = WB.getConcurrentGCPhases();

    54 

    55         List<String> expectedList = Arrays.asList(expectedPhases);

    56         List<String> actualList = Arrays.asList(actualPhases);

    57 

    58         Set<String> expected = toSet(expectedList, "Expected");

    59         Set<String> actual = toSet(actualList, "Actual");

    60 

    61         expected.removeAll(actualList);

    62         actual.removeAll(expectedList);

    63 

    64         boolean match = true;

    65         if (!expected.isEmpty()) {

    66             match = false;

    67             System.out.println("Unexpected phases:");

    68             for (String s: expected) {

    69                 System.out.println("  " + s);

    70             }

    71         }

    72         if (!actual.isEmpty()) {

    73             match = false;

    74             System.out.println("Expected but missing phases:");

    75             for (String s: actual) {

    76                 System.out.println("  " + s);

    77             }

    78         }

    79         if (!match) {

    80             throw new RuntimeException("Mismatch between expected and actual phases");

    81         }

    82     }

    83 

    84     public static void check(String gcName, String[] phases) throws Exception {

    85         // Verify supported.

    86         if (!WB.supportsConcurrentGCPhaseControl()) {

    87             throw new RuntimeException(

    88                 gcName + " unexpectedly missing phase control support");

    89         }

    90 

    91         checkPhases(phases);

    92 

    93         // Verify IllegalArgumentException thrown by request attempt

    94         // with unknown phase.

    95         boolean illegalArgumentThrown = false;

    96         try {

    97             WB.requestConcurrentGCPhase("UNKNOWN PHASE");

    98         } catch (IllegalArgumentException e) {

    99             // Expected.

   100             illegalArgumentThrown = true;

   101         } catch (Exception e) {

   102             throw new RuntimeException(

   103                 gcName + ": Unexpected exception when requesting unknown phase: " + e.toString());

   104         }

   105         if (!illegalArgumentThrown) {

   106             throw new RuntimeException(

   107                 gcName + ": No exception when requesting unknown phase");

   108         }

   109     }

   110 }

   111