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24 
25 #ifndef SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
26 #define SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
27 
28 #include "classfile/placeholders.hpp"
29 #include "utilities/hashtable.hpp"
30 
31 class ClassLoaderData;
32 class LoaderConstraintEntry;
33 class Symbol;
34 
35 class LoaderConstraintTable : public Hashtable<InstanceKlass*, mtClass> {
36 
37 private:
38   LoaderConstraintEntry** find_loader_constraint(Symbol* name,
39                                                  Handle loader);
40 
41 public:
42 
43   LoaderConstraintTable(int table_size);
44 
45   LoaderConstraintEntry* new_entry(unsigned int hash, Symbol* name,
46                                    InstanceKlass* klass, int num_loaders,
47                                    int max_loaders);
48   void free_entry(LoaderConstraintEntry *entry);
49 
bucket(int i) const50   LoaderConstraintEntry* bucket(int i) const {
51     return (LoaderConstraintEntry*)Hashtable<InstanceKlass*, mtClass>::bucket(i);
52   }
53 
bucket_addr(int i)54   LoaderConstraintEntry** bucket_addr(int i) {
55     return (LoaderConstraintEntry**)Hashtable<InstanceKlass*, mtClass>::bucket_addr(i);
56   }
57 
58   // Check class loader constraints
59   bool add_entry(Symbol* name, InstanceKlass* klass1, Handle loader1,
60                                     InstanceKlass* klass2, Handle loader2);
61 
62   // Note:  The main entry point for this module is via SystemDictionary.
63   // SystemDictionary::check_signature_loaders(Symbol* signature,
64   //                                           Handle loader1, Handle loader2,
65   //                                           bool is_method, TRAPS)
66 
67   InstanceKlass* find_constrained_klass(Symbol* name, Handle loader);
68 
69   // Class loader constraints
70 
71   void ensure_loader_constraint_capacity(LoaderConstraintEntry *p, int nfree);
72   void extend_loader_constraint(LoaderConstraintEntry* p, Handle loader,
73                                 InstanceKlass* klass);
74   void merge_loader_constraints(LoaderConstraintEntry** pp1,
75                                 LoaderConstraintEntry** pp2, InstanceKlass* klass);
76 
77   bool check_or_update(InstanceKlass* k, Handle loader, Symbol* name);
78 
79   void purge_loader_constraints();
80 
81   void verify(PlaceholderTable* placeholders);
82   void print_on(outputStream* st) const;
83 };
84 
85 class LoaderConstraintEntry : public HashtableEntry<InstanceKlass*, mtClass> {
86 private:
87   Symbol*                _name;                   // class name
88   int                    _num_loaders;
89   int                    _max_loaders;
90   // Loader constraints enforce correct linking behavior.
91   // Thus, it really operates on ClassLoaderData which represents linking domain,
92   // not class loaders.
93   ClassLoaderData**              _loaders;                // initiating loaders
94 
95 public:
96 
klass()97   InstanceKlass* klass() { return literal(); }
klass_addr()98   InstanceKlass** klass_addr() { return literal_addr(); }
set_klass(InstanceKlass * k)99   void set_klass(InstanceKlass* k) { set_literal(k); }
100 
next()101   LoaderConstraintEntry* next() {
102     return (LoaderConstraintEntry*)HashtableEntry<InstanceKlass*, mtClass>::next();
103   }
104 
next_addr()105   LoaderConstraintEntry** next_addr() {
106     return (LoaderConstraintEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr();
107   }
set_next(LoaderConstraintEntry * next)108   void set_next(LoaderConstraintEntry* next) {
109     HashtableEntry<InstanceKlass*, mtClass>::set_next(next);
110   }
111 
name()112   Symbol* name() { return _name; }
set_name(Symbol * name)113   void set_name(Symbol* name) {
114     _name = name;
115     if (name != NULL) name->increment_refcount();
116   }
117 
num_loaders()118   int num_loaders() { return _num_loaders; }
set_num_loaders(int i)119   void set_num_loaders(int i) { _num_loaders = i; }
120 
max_loaders()121   int max_loaders() { return _max_loaders; }
set_max_loaders(int i)122   void set_max_loaders(int i) { _max_loaders = i; }
123 
loaders()124   ClassLoaderData** loaders() { return _loaders; }
set_loaders(ClassLoaderData ** loaders)125   void set_loaders(ClassLoaderData** loaders) { _loaders = loaders; }
126 
loader_data(int i)127   ClassLoaderData* loader_data(int i) { return _loaders[i]; }
set_loader_data(int i,ClassLoaderData * p)128   void set_loader_data(int i, ClassLoaderData* p) { _loaders[i] = p; }
129   // convenience
130   void set_loader(int i, oop p);
131 };
132 
133 #endif // SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
134