interface/wx/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
  11     A smart pointer with non-intrusive reference counting. It is modeled after
  12     @c boost::shared_ptr<> and can be used with STL containers and wxVector<T> -
  13     unlike @c std::auto_ptr<> and wxScopedPtr<T>.
  14
  15     @library{wxbase}
  16     @category{smartpointers}
  17
  18     @see wxScopedPtr<T>, wxWeakRef<T>, wxObjectDataPtr<T>
  19 */
  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     wxEXPLICIT wxSharedPtr(T* ptr = NULL);
  32
  33     /**
  34         Copy constructor.
  35     */
  36     wxSharedPtr(const wxSharedPtr<T>& tocopy);
  37
  38     /**
  39         Destructor.
  40     */
  41     ~wxSharedPtr();
  42
  43     /**
  44         Returns pointer to its object or @NULL.
  45     */
  46     T* get() const;
  47
  48     /**
  49         Conversion to a boolean expression (in a variant which is not
  50         convertable to anything but a boolean expression).
  51
  52         If this class contains a valid pointer it will return @true, if it contains
  53         a @NULL pointer it will return @false.
  54     */
  55     operator unspecified_bool_type() const;
  56
  57     /**
  58         Returns a reference to the object.
  59
  60         If the internal pointer is @NULL this method will cause an assert in debug mode.
  61     */
  62     T operator*() const;
  63
  64     /**
  65         Returns pointer to its object or @NULL.
  66     */
  67     T* operator->() const;
  68
  69     /**
  70         Assignment operator.
  71
  72         Releases any previously held pointer and creates a reference to @a ptr.
  73     */
  74     wxSharedPtr<T>& operator=(T* ptr);
  75
  76     /**
  77         Assignment operator.
  78
  79         Releases any previously held pointer and creates a reference to the
  80         same object as @a topcopy.
  81     */
  82     wxSharedPtr<T>& operator=(const wxSharedPtr<T>& tocopy);
  83
  84     /**
  85         Reset pointer to @a ptr.
  86
  87         If the reference count of the previously owned pointer was 1 it will be deleted.
  88     */
  89     void reset(T* ptr = NULL);
  90
  91     /**
  92         Returns @true if this is the only pointer pointing to its object.
  93     */
  94     bool unique() const;
  95
  96     /**
  97         Returns the number of pointers pointing to its object.
  98     */
  99     long use_count() const;
 100 };
 101