dictionary.hpp revision 0:a61af66fc99e 
1/*
2 * Copyright 2003-2006 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
25class DictionaryEntry;
26
27//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28// The data structure for the system dictionary (and the shared system
29// dictionary).
30
31class Dictionary : public TwoOopHashtable {
32  friend class VMStructs;
33private:
34  // current iteration index.
35  static int                    _current_class_index;
36  // pointer to the current hash table entry.
37  static DictionaryEntry*       _current_class_entry;
38
39  DictionaryEntry* get_entry(int index, unsigned int hash,
40                             symbolHandle name, Handle loader);
41
42  DictionaryEntry* bucket(int i) {
43    return (DictionaryEntry*)Hashtable::bucket(i);
44  }
45
46  // The following method is not MT-safe and must be done under lock.
47  DictionaryEntry** bucket_addr(int i) {
48    return (DictionaryEntry**)Hashtable::bucket_addr(i);
49  }
50
51  void add_entry(int index, DictionaryEntry* new_entry) {
52    Hashtable::add_entry(index, (HashtableEntry*)new_entry);
53  }
54
55
56public:
57  Dictionary(int table_size);
58  Dictionary(int table_size, HashtableBucket* t, int number_of_entries);
59
60  DictionaryEntry* new_entry(unsigned int hash, klassOop klass, oop loader);
61
62  DictionaryEntry* new_entry();
63
64  void free_entry(DictionaryEntry* entry);
65
66  void add_klass(symbolHandle class_name, Handle class_loader,KlassHandle obj);
67
68  klassOop find_class(int index, unsigned int hash,
69                      symbolHandle name, Handle loader);
70
71  klassOop find_shared_class(int index, unsigned int hash, symbolHandle name);
72
73  // Compiler support
74  klassOop try_get_next_class();
75
76  // GC support
77
78  void oops_do(OopClosure* f);
79  void always_strong_classes_do(OopClosure* blk);
80  void classes_do(void f(klassOop));
81  void classes_do(void f(klassOop, TRAPS), TRAPS);
82  void classes_do(void f(klassOop, oop));
83  void classes_do(void f(klassOop, oop, TRAPS), TRAPS);
84
85  void methods_do(void f(methodOop));
86
87
88  // Classes loaded by the bootstrap loader are always strongly reachable.
89  // If we're not doing class unloading, all classes are strongly reachable.
90  static bool is_strongly_reachable(oop class_loader, oop klass) {
91    assert (klass != NULL, "should have non-null klass");
92    return (class_loader == NULL || !ClassUnloading);
93  }
94
95  // Unload (that is, break root links to) all unmarked classes and
96  // loaders.  Returns "true" iff something was unloaded.
97  bool do_unloading(BoolObjectClosure* is_alive);
98
99  // Protection domains
100  klassOop find(int index, unsigned int hash, symbolHandle name,
101                Handle loader, Handle protection_domain, TRAPS);
102  bool is_valid_protection_domain(int index, unsigned int hash,
103                                  symbolHandle name, Handle class_loader,
104                                  Handle protection_domain);
105  void add_protection_domain(int index, unsigned int hash,
106                             instanceKlassHandle klass, Handle loader,
107                             Handle protection_domain, TRAPS);
108
109  // Sharing support
110  void dump(SerializeOopClosure* soc);
111  void restore(SerializeOopClosure* soc);
112  void reorder_dictionary();
113
114
115#ifndef PRODUCT
116  void print();
117#endif
118  void verify();
119};
120
121// The following classes can be in dictionary.cpp, but we need these
122// to be in header file so that SA's vmStructs can access.
123
124class ProtectionDomainEntry :public CHeapObj {
125  friend class VMStructs;
126 public:
127  ProtectionDomainEntry* _next;
128  oop                    _protection_domain;
129
130  ProtectionDomainEntry(oop protection_domain, ProtectionDomainEntry* next) {
131    _protection_domain = protection_domain;
132    _next              = next;
133  }
134
135  ProtectionDomainEntry* next() { return _next; }
136  oop protection_domain() { return _protection_domain; }
137};
138
139// An entry in the system dictionary, this describes a class as
140// { klassOop, loader, protection_domain }.
141
142class DictionaryEntry : public HashtableEntry {
143  friend class VMStructs;
144 private:
145  // Contains the set of approved protection domains that can access
146  // this system dictionary entry.
147  ProtectionDomainEntry* _pd_set;
148  oop                    _loader;
149
150
151 public:
152  // Tells whether a protection is in the approved set.
153  bool contains_protection_domain(oop protection_domain) const;
154  // Adds a protection domain to the approved set.
155  void add_protection_domain(oop protection_domain);
156
157  klassOop klass() const { return (klassOop)literal(); }
158  klassOop* klass_addr() { return (klassOop*)literal_addr(); }
159
160  DictionaryEntry* next() const {
161    return (DictionaryEntry*)HashtableEntry::next();
162  }
163
164  DictionaryEntry** next_addr() {
165    return (DictionaryEntry**)HashtableEntry::next_addr();
166  }
167
168  oop loader() const { return _loader; }
169  void set_loader(oop loader) { _loader = loader; }
170  oop* loader_addr() { return &_loader; }
171
172  ProtectionDomainEntry* pd_set() const { return _pd_set; }
173  void set_pd_set(ProtectionDomainEntry* pd_set) { _pd_set = pd_set; }
174
175  bool has_protection_domain() { return _pd_set != NULL; }
176
177  // Tells whether the initiating class' protection can access the this _klass
178  bool is_valid_protection_domain(Handle protection_domain) {
179    if (!ProtectionDomainVerification) return true;
180    if (!SystemDictionary::has_checkPackageAccess()) return true;
181
182    return protection_domain() == NULL
183         ? true
184         : contains_protection_domain(protection_domain());
185  }
186
187
188  void protection_domain_set_oops_do(OopClosure* f) {
189    for (ProtectionDomainEntry* current = _pd_set;
190                                current != NULL;
191                                current = current->_next) {
192      f->do_oop(&(current->_protection_domain));
193    }
194  }
195
196  void verify_protection_domain_set() {
197    for (ProtectionDomainEntry* current = _pd_set;
198                                current != NULL;
199                                current = current->_next) {
200      current->_protection_domain->verify();
201    }
202  }
203
204  bool equals(symbolOop class_name, oop class_loader) const {
205    klassOop klass = (klassOop)literal();
206    return (instanceKlass::cast(klass)->name() == class_name &&
207            _loader == class_loader);
208  }
209
210  void print() {
211    int count = 0;
212    for (ProtectionDomainEntry* current = _pd_set;
213                                current != NULL;
214                                current = current->_next) {
215      count++;
216    }
217    tty->print_cr("pd set = #%d", count);
218  }
219};
220