1 /*

     2  * Copyright 2005 Sun Microsystems, Inc.  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.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

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

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

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

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

    15  * accompanied this code).

    16  *

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

    18  * 2 along with this work; if not, write to the Free Software Foundation,

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

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package com.sun.tools.jdi;

    27 

    28 import com.sun.jdi.*;

    29 

    30 public class MonitorInfoImpl extends MirrorImpl

    31     implements MonitorInfo, ThreadListener {

    32 

    33     /* Once false, monitorInfo should not be used.

    34      * access synchronized on (vm.state())

    35      */

    36     private boolean isValid = true;

    37 

    38     ObjectReference monitor;

    39     ThreadReference thread;

    40     int  stack_depth;

    41 

    42     MonitorInfoImpl(VirtualMachine vm, ObjectReference mon,

    43                     ThreadReference thread, int dpth) {

    44         super(vm);

    45         this.monitor = mon;

    46         this.thread = thread;

    47         this.stack_depth = dpth;

    48     }

    49 

    50 

    51     /*

    52      * ThreadListener implementation

    53      * Must be synchronized since we must protect against

    54      * sending defunct (isValid == false) stack ids to the back-end.

    55      */

    56     public boolean threadResumable(ThreadAction action) {

    57         synchronized (vm.state()) {

    58             if (isValid) {

    59                 isValid = false;

    60                 return false;   /* remove this stack frame as a listener */

    61             } else {

    62                 throw new InternalException(

    63                                   "Invalid stack frame thread listener");

    64             }

    65         }

    66     }

    67 

    68     private void validateMonitorInfo() {

    69         if (!isValid) {

    70             throw new InvalidStackFrameException("Thread has been resumed");

    71         }

    72     }

    73 

    74     public ObjectReference monitor() {

    75         validateMonitorInfo();

    76         return monitor;

    77     }

    78 

    79     public int stackDepth() {

    80         validateMonitorInfo();

    81         return stack_depth;

    82     }

    83 

    84     public ThreadReference thread() {

    85         validateMonitorInfo();

    86         return thread;

    87     }

    88 }