1 /*
2 * Copyright 2001-2005 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.
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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 package sun.jvm.hotspot.memory;
26
27 import java.util.*;
28 import sun.jvm.hotspot.debugger.*;
29 import sun.jvm.hotspot.oops.*;
30 import sun.jvm.hotspot.runtime.*;
31 import sun.jvm.hotspot.types.*;
32
33 public class SystemDictionary {
34 private static AddressField dictionaryField;
35 private static AddressField sharedDictionaryField;
36 private static AddressField placeholdersField;
37 private static AddressField loaderConstraintTableField;
38 private static sun.jvm.hotspot.types.OopField javaSystemLoaderField;
39 private static int nofBuckets;
40
41 private static sun.jvm.hotspot.types.OopField objectKlassField;
42 private static sun.jvm.hotspot.types.OopField classLoaderKlassField;
43 private static sun.jvm.hotspot.types.OopField stringKlassField;
44 private static sun.jvm.hotspot.types.OopField systemKlassField;
45 private static sun.jvm.hotspot.types.OopField threadKlassField;
46 private static sun.jvm.hotspot.types.OopField threadGroupKlassField;
47
48 static {
49 VM.registerVMInitializedObserver(new Observer() {
50 public void update(Observable o, Object data) {
51 initialize(VM.getVM().getTypeDataBase());
52 }
53 });
54 }
55
56 private static synchronized void initialize(TypeDataBase db) {
57 Type type = db.lookupType("SystemDictionary");
58
59 dictionaryField = type.getAddressField("_dictionary");
60 sharedDictionaryField = type.getAddressField("_shared_dictionary");
61 placeholdersField = type.getAddressField("_placeholders");
62 loaderConstraintTableField = type.getAddressField("_loader_constraints");
63 javaSystemLoaderField = type.getOopField("_java_system_loader");
64 nofBuckets = db.lookupIntConstant("SystemDictionary::_nof_buckets").intValue();
65
66 objectKlassField = type.getOopField("_object_klass");
67 classLoaderKlassField = type.getOopField("_classloader_klass");
68 stringKlassField = type.getOopField("_string_klass");
69 systemKlassField = type.getOopField("_system_klass");
70 threadKlassField = type.getOopField("_thread_klass");
71 threadGroupKlassField = type.getOopField("_threadGroup_klass");
72 }
73
74 public Dictionary dictionary() {
75 Address tmp = dictionaryField.getValue();
76 return (Dictionary) VMObjectFactory.newObject(Dictionary.class, tmp);
77 }
78
79 public Dictionary sharedDictionary() {
80 Address tmp = sharedDictionaryField.getValue();
81 return (Dictionary) VMObjectFactory.newObject(Dictionary.class, tmp);
82 }
83
84 public PlaceholderTable placeholders() {
85 Address tmp = placeholdersField.getValue();
86 return (PlaceholderTable) VMObjectFactory.newObject(PlaceholderTable.class, tmp);
87 }
88
89 public LoaderConstraintTable constraints() {
90 Address tmp = placeholdersField.getValue();
91 return (LoaderConstraintTable) VMObjectFactory.newObject(LoaderConstraintTable.class, tmp);
92 }
93
94 // few well known classes -- not all are added here.
95 // add more if needed.
96 public static InstanceKlass getThreadKlass() {
97 return (InstanceKlass) newOop(threadKlassField.getValue());
98 }
99
100 public static InstanceKlass getThreadGroupKlass() {
101 return (InstanceKlass) newOop(threadGroupKlassField.getValue());
102 }
103
104 public static InstanceKlass getObjectKlass() {
105 return (InstanceKlass) newOop(objectKlassField.getValue());
106 }
107
108 public static InstanceKlass getStringKlass() {
109 return (InstanceKlass) newOop(stringKlassField.getValue());
110 }
111
112 public static InstanceKlass getClassLoaderKlass() {
113 return (InstanceKlass) newOop(classLoaderKlassField.getValue());
114 }
115
116 public static InstanceKlass getSystemKlass() {
117 return (InstanceKlass) newOop(systemKlassField.getValue());
118 }
119
120 public InstanceKlass getAbstractOwnableSynchronizerKlass() {
121 return (InstanceKlass) find("java/util/concurrent/locks/AbstractOwnableSynchronizer",
122 null, null);
123 }
124
125 public static Oop javaSystemLoader() {
126 return newOop(javaSystemLoaderField.getValue());
127 }
128
129 public static int getNumOfBuckets() {
130 return nofBuckets;
131 }
132
133 private static Oop newOop(OopHandle handle) {
134 return VM.getVM().getObjectHeap().newOop(handle);
135 }
136
137 /** Lookup an already loaded class. If not found null is returned. */
138 public Klass find(String className, Oop classLoader, Oop protectionDomain) {
139 Symbol sym = VM.getVM().getSymbolTable().probe(className);
140 if (sym == null) return null;
141 return find(sym, classLoader, protectionDomain);
142 }
143
144 /** Lookup an already loaded class. If not found null is returned. */
145 public Klass find(Symbol className, Oop classLoader, Oop protectionDomain) {
146 Dictionary dict = dictionary();
147 long hash = dict.computeHash(className, classLoader);
148 int index = dict.hashToIndex(hash);
149 return dict.find(index, hash, className, classLoader, protectionDomain);
150 }
151
152 /** Interface for iterating through all classes in dictionary */
153 public static interface ClassVisitor {
154 public void visit(Klass k);
155 }
156
157 /** Interface for iterating through all classes and their class
158 loaders in dictionary */
159 public static interface ClassAndLoaderVisitor {
160 public void visit(Klass k, Oop loader);
161 }
162
163 /** Iterate over all klasses - including object, primitive
164 array klasses */
165 public void allClassesDo(final ClassVisitor v) {
166 ClassVisitor visitor = new ClassVisitor() {
167 public void visit(Klass k) {
168 for (Klass l = k; l != null; l = l.arrayKlassOrNull()) {
169 v.visit(l);
170 }
171 }
172 };
173 classesDo(visitor);
174 VM.getVM().getUniverse().basicTypeClassesDo(visitor);
175 }
176
177 /** Iterate over all klasses in dictionary; just the classes from
178 declaring class loaders */
179 public void classesDo(ClassVisitor v) {
180 dictionary().classesDo(v);
181 }
182
183 /** All classes, and their class loaders */
184 public void classesDo(ClassAndLoaderVisitor v) {
185 dictionary().classesDo(v);
186 }
187
188 /** All array classes of primitive type, and their class loaders */
189 public void primArrayClassesDo(ClassAndLoaderVisitor v) {
190 placeholders().primArrayClassesDo(v);
191 }
192 }