loaderConstraints.hpp revision 3465:d2a62e0f25eb 
1/*
2 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. 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
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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.
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23 */
24
25#ifndef SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
26#define SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
27
28#include "classfile/dictionary.hpp"
29#include "classfile/placeholders.hpp"
30#include "utilities/hashtable.hpp"
31
32class LoaderConstraintEntry;
33
34class LoaderConstraintTable : public Hashtable<klassOop, mtClass> {
35  friend class VMStructs;
36private:
37
38  enum Constants {
39    _loader_constraint_size = 107,                     // number of entries in constraint table
40    _nof_buckets            = 1009                     // number of buckets in hash table
41  };
42
43  LoaderConstraintEntry** find_loader_constraint(Symbol* name,
44                                                 Handle loader);
45
46public:
47
48  LoaderConstraintTable(int nof_buckets);
49
50  LoaderConstraintEntry* new_entry(unsigned int hash, Symbol* name,
51                                   klassOop klass, int num_loaders,
52                                   int max_loaders);
53  void free_entry(LoaderConstraintEntry *entry);
54
55  LoaderConstraintEntry* bucket(int i) {
56    return (LoaderConstraintEntry*)Hashtable<klassOop, mtClass>::bucket(i);
57  }
58
59  LoaderConstraintEntry** bucket_addr(int i) {
60    return (LoaderConstraintEntry**)Hashtable<klassOop, mtClass>::bucket_addr(i);
61  }
62
63  // GC support
64  void oops_do(OopClosure* f);
65
66  // Check class loader constraints
67  bool add_entry(Symbol* name, klassOop klass1, Handle loader1,
68                                    klassOop klass2, Handle loader2);
69
70  // Note:  The main entry point for this module is via SystemDictionary.
71  // SystemDictionary::check_signature_loaders(Symbol* signature,
72  //                                           Handle loader1, Handle loader2,
73  //                                           bool is_method, TRAPS)
74
75  klassOop find_constrained_klass(Symbol* name, Handle loader);
76
77  // Class loader constraints
78
79  void ensure_loader_constraint_capacity(LoaderConstraintEntry *p, int nfree);
80  void extend_loader_constraint(LoaderConstraintEntry* p, Handle loader,
81                                klassOop klass);
82  void merge_loader_constraints(LoaderConstraintEntry** pp1,
83                                LoaderConstraintEntry** pp2, klassOop klass);
84
85  bool check_or_update(instanceKlassHandle k, Handle loader,
86                              Symbol* name);
87
88
89  void purge_loader_constraints(BoolObjectClosure* is_alive);
90
91  void verify(Dictionary* dictionary, PlaceholderTable* placeholders);
92#ifndef PRODUCT
93  void print();
94#endif
95};
96
97class LoaderConstraintEntry : public HashtableEntry<klassOop, mtClass> {
98  friend class VMStructs;
99private:
100  Symbol*                _name;                   // class name
101  int                    _num_loaders;
102  int                    _max_loaders;
103  oop*                   _loaders;                // initiating loaders
104
105public:
106
107  klassOop klass() { return literal(); }
108  klassOop* klass_addr() { return literal_addr(); }
109  void set_klass(klassOop k) { set_literal(k); }
110
111  LoaderConstraintEntry* next() {
112    return (LoaderConstraintEntry*)HashtableEntry<klassOop, mtClass>::next();
113  }
114
115  LoaderConstraintEntry** next_addr() {
116    return (LoaderConstraintEntry**)HashtableEntry<klassOop, mtClass>::next_addr();
117  }
118  void set_next(LoaderConstraintEntry* next) {
119    HashtableEntry<klassOop, mtClass>::set_next(next);
120  }
121
122  Symbol* name() { return _name; }
123  void set_name(Symbol* name) {
124    _name = name;
125    if (name != NULL) name->increment_refcount();
126  }
127
128  int num_loaders() { return _num_loaders; }
129  void set_num_loaders(int i) { _num_loaders = i; }
130
131  int max_loaders() { return _max_loaders; }
132  void set_max_loaders(int i) { _max_loaders = i; }
133
134  oop* loaders() { return _loaders; }
135  void set_loaders(oop* loaders) { _loaders = loaders; }
136
137  oop loader(int i) { return _loaders[i]; }
138  oop* loader_addr(int i) { return &_loaders[i]; }
139  void set_loader(int i, oop p) { _loaders[i] = p; }
140
141};
142
143#endif // SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
144