1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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13  * accompanied this code).
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24 
25 package sun.jvm.hotspot.runtime;
26 
27 import java.util.*;
28 import sun.jvm.hotspot.debugger.*;
29 import sun.jvm.hotspot.types.*;
30 import sun.jvm.hotspot.utilities.Observable;
31 import sun.jvm.hotspot.utilities.Observer;
32 
33 // The OSThread class holds OS-specific thread information.  It is equivalent
34 // to the sys_thread_t structure of the classic JVM implementation.
35 public class OSThread extends VMObject {
36     private static Field threadIdField;
37     private static CIntegerField threadStateField;
38 
39     // ThreadStates read from underlying process
40     private static int ALLOCATED;
41     private static int INITIALIZED;
42     private static int RUNNABLE;
43     private static int MONITOR_WAIT;
44     private static int CONDVAR_WAIT;
45     private static int OBJECT_WAIT;
46     private static int BREAKPOINTED;
47     private static int SLEEPING;
48     private static int ZOMBIE;
49 
50     static {
VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } })51         VM.registerVMInitializedObserver(new Observer() {
52             public void update(Observable o, Object data) {
53                 initialize(VM.getVM().getTypeDataBase());
54             }
55         });
56     }
57 
initialize(TypeDataBase db)58     private static synchronized void initialize(TypeDataBase db) {
59         Type type = db.lookupType("OSThread");
60         threadIdField = type.getField("_thread_id");
61         threadStateField = type.getCIntegerField("_state");
62 
63         ALLOCATED = db.lookupIntConstant("ALLOCATED").intValue();
64         INITIALIZED = db.lookupIntConstant("INITIALIZED").intValue();
65         RUNNABLE = db.lookupIntConstant("RUNNABLE").intValue();
66         MONITOR_WAIT = db.lookupIntConstant("MONITOR_WAIT").intValue();
67         CONDVAR_WAIT = db.lookupIntConstant("CONDVAR_WAIT").intValue();
68         OBJECT_WAIT = db.lookupIntConstant("OBJECT_WAIT").intValue();
69         BREAKPOINTED = db.lookupIntConstant("BREAKPOINTED").intValue();
70         SLEEPING = db.lookupIntConstant("SLEEPING").intValue();
71         ZOMBIE = db.lookupIntConstant("ZOMBIE").intValue();
72     }
73 
OSThread(Address addr)74     public OSThread(Address addr) {
75         super(addr);
76     }
77 
threadId()78     public int threadId() {
79         return threadIdField.getJInt(addr);
80     }
81 
getThreadState()82     public ThreadState getThreadState() {
83         int val = (int)threadStateField.getValue(addr);
84         if (val ==  ALLOCATED) {
85             return ThreadState.ALLOCATED;
86         } else if (val ==  INITIALIZED) {
87             return ThreadState.INITIALIZED;
88         } else if (val ==  RUNNABLE) {
89             return ThreadState.RUNNABLE;
90         } else if (val ==  MONITOR_WAIT) {
91             return ThreadState.MONITOR_WAIT;
92         } else if (val ==  CONDVAR_WAIT) {
93             return ThreadState.CONDVAR_WAIT;
94         } else if (val ==  OBJECT_WAIT) {
95             return ThreadState.OBJECT_WAIT;
96         } else if (val ==  BREAKPOINTED) {
97             return ThreadState.BREAKPOINTED;
98         } else if (val ==  SLEEPING) {
99             return ThreadState.SLEEPING;
100         } else if (val ==  ZOMBIE) {
101             return ThreadState.ZOMBIE;
102         } else {
103             throw new RuntimeException("Illegal thread state " + val);
104         }
105     }
106 }
107