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24 
25 #ifndef SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP
26 #define SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP
27 #include "jfr/utilities/jfrAllocation.hpp"
28 #include "jfr/utilities/jfrDoublyLinkedList.hpp"
29 
30 class ObjectSample;
31 
32 class SampleList : public JfrCHeapObj {
33   typedef JfrDoublyLinkedList<ObjectSample> List;
34  private:
35   List _free_list;
36   List _in_use_list;
37   const ObjectSample* _last_resolved;
38   mutable size_t _allocated;
39   const size_t _limit;
40   const size_t _cache_size;
41 
42   void populate_cache();
43   ObjectSample* newSample() const;
44   void link(ObjectSample* sample);
45   void unlink(ObjectSample* sample);
46   void deallocate_samples(List& list);
47   void reset(ObjectSample* sample);
48 
49  public:
50   SampleList(size_t limit, size_t cache_size = 0);
51   ~SampleList();
52 
53   ObjectSample* get();
54   ObjectSample* first() const;
55   ObjectSample* last() const;
56   const ObjectSample* last_resolved() const;
57   void set_last_resolved(const ObjectSample* sample);
58   void release(ObjectSample* sample);
59   ObjectSample* reuse(ObjectSample* sample);
60   bool is_full() const;
61   size_t count() const;
62 };
63 
64 #endif // SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP
65