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 

    25 package sun.jvm.hotspot.runtime;

    26 

    27 import java.util.*;

    28 

    29 public class ThreadStackTrace {

    30     private JavaThread                        thread;

    31     private int                               depth;  // number of stack frames added

    32     private ArrayList<StackFrameInfo>         frames;

    33 

    34     public ThreadStackTrace(JavaThread t) {

    35         this.thread = t;

    36         this.depth = 0;

    37         this.frames = new ArrayList<StackFrameInfo>();

    38     }

    39 

    40     public int getStackDepth() {

    41         return depth;

    42     }

    43 

    44     public StackFrameInfo stackFrameAt(int index) {

    45         return frames.get(index);

    46     }

    47 

    48     public void dumpStack(int maxDepth) {

    49         if (!thread.isJavaThread()) {

    50             System.out.println("dumpStack: not java Thread returning");

    51             return;

    52         }

    53         try {

    54             for (JavaVFrame vf = thread.getLastJavaVFrameDbg(); vf != null; vf = vf.javaSender()) {

    55                 StackFrameInfo frame = new StackFrameInfo(vf);

    56                 frames.add(frame);

    57                 depth++;

    58 

    59                 if (maxDepth > 0 && depth == maxDepth) {

    60                     // Skip frames if more than maxDepth

    61                     break;

    62                 }

    63             }

    64         } catch (Exception e) {

    65             System.out.println("Error occurred during stack walking:");

    66             e.printStackTrace();

    67         }

    68     }

    69 }