1 /*

     2  * Copyright (c) 2013, 2016, 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 import sun.jvmstat.monitor.Monitor;

    25 import sun.jvmstat.monitor.MonitorException;

    26 import sun.jvmstat.monitor.MonitoredHost;

    27 import sun.jvmstat.monitor.MonitoredVm;

    28 import sun.jvmstat.monitor.VmIdentifier;

    29 import jdk.test.lib.process.ProcessTools;

    30 

    31 /**

    32  * PerfCounters can be used to get a performance counter from the currently

    33  * executing VM.

    34  *

    35  * Throws a runtime exception if an error occurs while communicating with the

    36  * currently executing VM.

    37  */

    38 public class PerfCounters {

    39     private final static MonitoredVm vm;

    40 

    41     static {

    42         try {

    43             String pid = Long.toString(ProcessTools.getProcessId());

    44             VmIdentifier vmId = new VmIdentifier(pid);

    45             MonitoredHost host = MonitoredHost.getMonitoredHost(vmId);

    46             vm = host.getMonitoredVm(vmId);

    47         } catch (Exception e) {

    48             throw new RuntimeException("Could not connect to the VM");

    49         }

    50     }

    51 

    52     /**

    53      * Returns the performance counter with the given name.

    54      *

    55      * @param name The name of the performance counter.

    56      * @throws IllegalArgumentException If no counter with the given name exists.

    57      * @throws MonitorException If an error occurs while communicating with the VM.

    58      * @return The performance counter with the given name.

    59      */

    60     public static PerfCounter findByName(String name)

    61         throws MonitorException, IllegalArgumentException {

    62         Monitor m = vm.findByName(name);

    63         if (m == null) {

    64             throw new IllegalArgumentException("Did not find a performance counter with name " + name);

    65         }

    66         return new PerfCounter(m, name);

    67     }

    68 }