interface/ptr_shrd.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        ptr_shrd.h
   3 // Purpose:     interface of wxSharedPtr<T>
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @wxheader{ptr_shrd.h}
  11
  12     A smart pointer with non-intrusive reference counting. It is modeled after
  13     @c boost::shared_ptr and can be used with STL containers and wxVector<T> -
  14     unlike @c std::auto_ptr and wxScopedPtr<T>.
  15
  16     @library{wxbase}
  17     @category{smartpointers}
  18
  19     @see wxScopedPtr<T>, wxWeakRef<T>, wxObjectDataPtr<T>
  20 */
  21 template<typename T>
  22 class wxSharedPtr<T>
  23 {
  24 public:
  25     /**
  26         Constructor.
  27
  28         Creates shared pointer from the raw pointer @a ptr and takes ownership
  29         of it.
  30     */
  31     wxSharedPtr(T* ptr = NULL);
  32
  33     /// Copy constructor.
  34     wxSharedPtr(const wxSharedPtr<T>& tocopy);
  35
  36     /**
  37         Destructor.
  38     */
  39     ~wxSharedPtr();
  40
  41     /**
  42         Returns pointer to its object or @NULL.
  43     */
  44     T* get() const;
  45
  46     /**
  47         Conversion to a boolean expression (in a variant which is not
  48         convertable to anything but a boolean expression). If this class
  49         contains a valid pointer it will return @e @true, if it contains
  50         a @NULL pointer it will return @e @false.
  51     */
  52     operator unspecified_bool_type() const;
  53
  54     /**
  55         Returns a reference to the object. If the internal pointer is @NULL
  56         this method will cause an assert in debug mode.
  57     */
  58     T operator*() const;
  59
  60     /**
  61         Returns pointer to its object or @NULL.
  62     */
  63     T* operator-() const;
  64
  65     /**
  66         Assignment operator. Releases any previously held pointer
  67         and creates a reference to @e ptr.
  68     */
  69     wxSharedPtr& operator operator=(T* ptr);
  70
  71     /**
  72         Reset pointer to @e ptr. If the reference count of the
  73         previously owned pointer was 1 it will be deleted.
  74     */
  75     void reset(T* ptr = NULL);
  76
  77     /**
  78         Returns @true if this is the only pointer pointing to its object.
  79     */
  80     bool unique() const;
  81
  82     /**
  83         Returns the number of pointers pointing to its object.
  84     */
  85     long use_count() const;
  86 };
  87