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// Copyright 2011 Google Inc. All Rights Reserved.
#ifndef ART_SRC_INTERN_TABLE_H_
#define ART_SRC_INTERN_TABLE_H_
#include "unordered_map.h"
#include "heap.h"
#include "mutex.h"
#include "object.h"
namespace art {
/**
* Used to intern strings.
*
* There are actually two tables: one that holds strong references to its strings, and one that
* holds weak references. The former is used for string literals, for which there is an effective
* reference from the constant pool. The latter is used for strings interned at runtime via
* String.intern. Some code (XML parsers being a prime example) relies on being able to intern
* arbitrarily many strings for the duration of a parse without permanently increasing the memory
* footprint.
*/
class InternTable {
public:
InternTable();
// Interns a potentially new string in the 'strong' table. (See above.)
String* InternStrong(int32_t utf16_length, const char* utf8_data);
// Interns a potentially new string in the 'strong' table. (See above.)
String* InternStrong(const char* utf8_data);
// Interns a potentially new string in the 'strong' table. (See above.)
String* InternStrong(String* s);
// Interns a potentially new string in the 'weak' table. (See above.)
String* InternWeak(String* s);
// Register a String trusting that it is safe to intern.
// Used when reinitializing InternTable from an image.
void RegisterStrong(String* s);
void SweepInternTableWeaks(Heap::IsMarkedTester is_marked, void* arg);
bool ContainsWeak(String* s);
size_t Size() const;
void VisitRoots(Heap::RootVisitor* visitor, void* arg) const;
private:
typedef std::tr1::unordered_multimap<int32_t, String*> Table;
String* Insert(String* s, bool is_strong);
String* Lookup(Table& table, String* s, uint32_t hash_code);
String* Insert(Table& table, String* s, uint32_t hash_code);
void Remove(Table& table, const String* s, uint32_t hash_code);
mutable Mutex intern_table_lock_;
Table strong_interns_;
Table weak_interns_;
};
} // namespace art
#endif // ART_SRC_CLASS_LINKER_H_