1 /*

     2  * Copyright (c) 2007, 2018, 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 nsk.monitoring.share.thread;

    25 

    26 /**

    27  * Locker thread is used to lock monitor on which BlockedThread's

    28  * waits.

    29  */

    30 public class LockerThread extends Thread {

    31         private String lock = new String("a lock");

    32         private Object ready = new Object();

    33         private Object lockit = new Object();

    34         private volatile boolean locked = false;

    35 

    36         public Object getLock() {

    37                 return lock;

    38         }

    39 

    40         public boolean isLocked() {

    41                 return locked;

    42         }

    43 

    44         public void waitState() {

    45                 synchronized (ready) {

    46                         while (!locked) {

    47                                 try {

    48                                         ready.wait();

    49                                 } catch (InterruptedException e) {

    50                                 }

    51                         }

    52                 }

    53 

    54                 ThreadUtils.waitThreadState(this, Thread.State.WAITING);

    55 

    56                 System.out.println("Locker thread reached WAITING state");

    57         }

    58 

    59         public void finish() {

    60                 locked = false;

    61                 synchronized (lockit) {

    62                         lockit.notifyAll();

    63                 }

    64         }

    65 

    66         public void run() {

    67                 synchronized (lock) {

    68                         synchronized (lockit) {

    69                                 synchronized (ready) {

    70                                         locked = true;

    71                                         ready.notifyAll();

    72                                 }

    73                                 while (locked) {

    74                                         try {

    75                                                 lockit.wait();

    76                                         } catch (InterruptedException e) {

    77                                         }

    78                                 }

    79                         }

    80                 }

    81 

    82                 System.out.println("Locker thread leaved WAITING state");

    83         }

    84 }