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24 
25 #ifndef SHARE_SERVICES_HEAPDUMPER_HPP
26 #define SHARE_SERVICES_HEAPDUMPER_HPP
27 
28 #include "memory/allocation.hpp"
29 #include "oops/oop.hpp"
30 #include "runtime/os.hpp"
31 
32 // HeapDumper is used to dump the java heap to file in HPROF binary format:
33 //
34 //  { HeapDumper dumper(true /* full GC before heap dump */);
35 //    if (dumper.dump("/export/java.hprof")) {
36 //      ResourceMark rm;
37 //      tty->print_cr("Dump failed: %s", dumper.error_as_C_string());
38 //    } else {
39 //      // dump succeeded
40 //    }
41 //  }
42 //
43 
44 class outputStream;
45 
46 class HeapDumper : public StackObj {
47  private:
48   char* _error;
49   bool _gc_before_heap_dump;
50   bool _oome;
51   elapsedTimer _t;
52 
HeapDumper(bool gc_before_heap_dump,bool oome)53   HeapDumper(bool gc_before_heap_dump, bool oome) :
54     _error(NULL), _gc_before_heap_dump(gc_before_heap_dump), _oome(oome) { }
55 
56   // string representation of error
error() const57   char* error() const                   { return _error; }
58   void set_error(char const* error);
59 
60   // internal timer.
timer()61   elapsedTimer* timer()                 { return &_t; }
62 
63   static void dump_heap(bool oome);
64 
65  public:
HeapDumper(bool gc_before_heap_dump)66   HeapDumper(bool gc_before_heap_dump) :
67     _error(NULL), _gc_before_heap_dump(gc_before_heap_dump), _oome(false) { }
68 
69   ~HeapDumper();
70 
71   // dumps the heap to the specified file, returns 0 if success.
72   // additional info is written to out if not NULL.
73   // compression >= 0 creates a gzipped file with the given compression level.
74   int dump(const char* path, outputStream* out = NULL, int compression = -1);
75 
76   // returns error message (resource allocated), or NULL if no error
77   char* error_as_C_string() const;
78 
79   static void dump_heap()    NOT_SERVICES_RETURN;
80 
81   static void dump_heap_from_oome()    NOT_SERVICES_RETURN;
82 };
83 
84 #endif // SHARE_SERVICES_HEAPDUMPER_HPP
85