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 import sun.jvm.hotspot.types.OopField; // resolve ambiguity with oops.OopField
33
34 // following needed for on-the-fly field construction:
35 import sun.jvm.hotspot.types.basic.BasicOopField;
36 import sun.jvm.hotspot.types.basic.BasicTypeDataBase;
37
38 public class SystemDictionary {
39 private static AddressField dictionaryField;
40 private static AddressField sharedDictionaryField;
41 private static AddressField placeholdersField;
42 private static AddressField loaderConstraintTableField;
43 private static OopField javaSystemLoaderField;
44 private static int nofBuckets;
45
46 private static OopField wellKnownKlasses;
47 private static OopField objectKlassField;
48 private static OopField classLoaderKlassField;
49 private static OopField stringKlassField;
50 private static OopField systemKlassField;
51 private static OopField threadKlassField;
52 private static OopField threadGroupKlassField;
53
54 static {
55 VM.registerVMInitializedObserver(new Observer() {
56 public void update(Observable o, Object data) {
57 initialize(VM.getVM().getTypeDataBase());
58 }
59 });
60 }
61
62 private static synchronized void initialize(TypeDataBase db) {
63 Type type = db.lookupType("SystemDictionary");
64
65 dictionaryField = type.getAddressField("_dictionary");
66 sharedDictionaryField = type.getAddressField("_shared_dictionary");
67 placeholdersField = type.getAddressField("_placeholders");
68 loaderConstraintTableField = type.getAddressField("_loader_constraints");
69 javaSystemLoaderField = type.getOopField("_java_system_loader");
70 nofBuckets = db.lookupIntConstant("SystemDictionary::_nof_buckets").intValue();
71
72 wellKnownKlasses = type.getOopField("_well_known_klasses[0]");
73 objectKlassField = findWellKnownKlass("object_klass", type, db);
74 classLoaderKlassField = findWellKnownKlass("classloader_klass", type, db);
75 stringKlassField = findWellKnownKlass("string_klass", type, db);
76 systemKlassField = findWellKnownKlass("system_klass", type, db);
77 threadKlassField = findWellKnownKlass("thread_klass", type, db);
78 threadGroupKlassField = findWellKnownKlass("threadGroup_klass", type, db);
79 }
80
81 private static OopField findWellKnownKlass(String indexName, Type type, TypeDataBase db) {
82 Address wkk = wellKnownKlasses.getStaticFieldAddress();
83 int index = db.lookupIntConstant("SystemDictionary::#"+indexName).intValue();
84 return new BasicOopField((BasicTypeDataBase)db, type, indexName, type,
85 true, index * db.getAddressSize(), wkk);
86 }
87
88 public Dictionary dictionary() {
89 Address tmp = dictionaryField.getValue();
90 return (Dictionary) VMObjectFactory.newObject(Dictionary.class, tmp);
91 }
92
93 public Dictionary sharedDictionary() {
94 Address tmp = sharedDictionaryField.getValue();
95 return (Dictionary) VMObjectFactory.newObject(Dictionary.class, tmp);
96 }
97
98 public PlaceholderTable placeholders() {
99 Address tmp = placeholdersField.getValue();
100 return (PlaceholderTable) VMObjectFactory.newObject(PlaceholderTable.class, tmp);
101 }
102
103 public LoaderConstraintTable constraints() {
104 Address tmp = placeholdersField.getValue();
105 return (LoaderConstraintTable) VMObjectFactory.newObject(LoaderConstraintTable.class, tmp);
106 }
107
108 // few well known classes -- not all are added here.
109 // add more if needed.
110 public static InstanceKlass getThreadKlass() {
111 return (InstanceKlass) newOop(threadKlassField.getValue());
112 }
113
114 public static InstanceKlass getThreadGroupKlass() {
115 return (InstanceKlass) newOop(threadGroupKlassField.getValue());
116 }
117
118 public static InstanceKlass getObjectKlass() {
119 return (InstanceKlass) newOop(objectKlassField.getValue());
120 }
121
122 public static InstanceKlass getStringKlass() {
123 return (InstanceKlass) newOop(stringKlassField.getValue());
124 }
125
126 public static InstanceKlass getClassLoaderKlass() {
127 return (InstanceKlass) newOop(classLoaderKlassField.getValue());
128 }
129
130 public static InstanceKlass getSystemKlass() {
131 return (InstanceKlass) newOop(systemKlassField.getValue());
132 }
133
134 public InstanceKlass getAbstractOwnableSynchronizerKlass() {
135 return (InstanceKlass) find("java/util/concurrent/locks/AbstractOwnableSynchronizer",
136 null, null);
137 }
138
139 public static Oop javaSystemLoader() {
140 return newOop(javaSystemLoaderField.getValue());
141 }
142
143 public static int getNumOfBuckets() {
144 return nofBuckets;
145 }
146
147 private static Oop newOop(OopHandle handle) {
148 return VM.getVM().getObjectHeap().newOop(handle);
149 }
150
151 /** Lookup an already loaded class. If not found null is returned. */
152 public Klass find(String className, Oop classLoader, Oop protectionDomain) {
153 Symbol sym = VM.getVM().getSymbolTable().probe(className);
154 if (sym == null) return null;
155 return find(sym, classLoader, protectionDomain);
156 }
157
158 /** Lookup an already loaded class. If not found null is returned. */
159 public Klass find(Symbol className, Oop classLoader, Oop protectionDomain) {
160 Dictionary dict = dictionary();
161 long hash = dict.computeHash(className, classLoader);
162 int index = dict.hashToIndex(hash);
163 return dict.find(index, hash, className, classLoader, protectionDomain);
164 }
165
166 /** Interface for iterating through all classes in dictionary */
167 public static interface ClassVisitor {
168 public void visit(Klass k);
169 }
170
171 /** Interface for iterating through all classes and their class
172 loaders in dictionary */
173 public static interface ClassAndLoaderVisitor {
174 public void visit(Klass k, Oop loader);
175 }
176
177 /** Iterate over all klasses - including object, primitive
178 array klasses */
179 public void allClassesDo(final ClassVisitor v) {
180 ClassVisitor visitor = new ClassVisitor() {
181 public void visit(Klass k) {
182 for (Klass l = k; l != null; l = l.arrayKlassOrNull()) {
183 v.visit(l);
184 }
185 }
186 };
187 classesDo(visitor);
188 VM.getVM().getUniverse().basicTypeClassesDo(visitor);
189 }
190
191 /** Iterate over all klasses in dictionary; just the classes from
192 declaring class loaders */
193 public void classesDo(ClassVisitor v) {
194 dictionary().classesDo(v);
195 }
196
197 /** All classes, and their class loaders */
198 public void classesDo(ClassAndLoaderVisitor v) {
199 dictionary().classesDo(v);
200 }
201
202 /** All array classes of primitive type, and their class loaders */
203 public void primArrayClassesDo(ClassAndLoaderVisitor v) {
204 placeholders().primArrayClassesDo(v);
205 }
206 }