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Java > Open Source Codes > Mtrace


1 /*
2  * @(#)Mtrace.java 1.3 05/11/17
3  *
4  * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * -Redistribution of source code must retain the above copyright notice, this
10  * list of conditions and the following disclaimer.
11  *
12  * -Redistribution in binary form must reproduce the above copyright notice,
13  * this list of conditions and the following disclaimer in the documentation
14  * and/or other materials provided with the distribution.
15  *
16  * Neither the name of Sun Microsystems, Inc. or the names of contributors may
17  * be used to endorse or promote products derived from this software without
18  * specific prior written permission.
19  *
20  * This software is provided "AS IS," without a warranty of any kind. ALL
21  * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
22  * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
23  * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
24  * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
25  * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
26  * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
27  * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
28  * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
29  * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
30  * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
31  *
32  * You acknowledge that this software is not designed, licensed or intended
33  * for use in the design, construction, operation or maintenance of any
34  * nuclear facility.
35  */
36
37
38 /* Java class to hold static methods which will be called in byte code
39  * injections of all class files.
40  */
41
42 public class Mtrace {
43  
44     /* Master switch that activates methods. */
45     
46     private static int engaged = 0;
47   
48     /* At the very beginning of every method, a call to method_entry()
49      * is injected.
50      */
51     
52     private static native void _method_entry(Object JavaDoc thr, int cnum, int mnum);
53     public static void method_entry(int cnum, int mnum)
54     {
55     if ( engaged != 0 ) {
56         _method_entry(Thread.currentThread(), cnum, mnum);
57     }
58     }
59     
60     /* Before any of the return bytecodes, a call to method_exit()
61      * is injected.
62      */
63     
64     private static native void _method_exit(Object JavaDoc thr, int cnum, int mnum);
65     public static void method_exit(int cnum, int mnum)
66     {
67     if ( engaged != 0 ) {
68         _method_exit(Thread.currentThread(), cnum, mnum);
69     }
70     }
71     
72 }
73
74
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