include/comphelper/weakbag.hxx

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  19
  20 #ifndef INCLUDED_COMPHELPER_WEAKBAG_HXX
  21 #define INCLUDED_COMPHELPER_WEAKBAG_HXX
  22
  23 #include "sal/config.h"
  24
  25 #include <list>
  26 #include "com/sun/star/uno/Reference.hxx"
  27 #include "cppuhelper/weakref.hxx"
  28 #include "osl/diagnose.h"
  29
  30 namespace comphelper {
  31
  32 /**
  33    A bag of UNO weak references.
  34 */
  35 template< typename T > class WeakBag {
  36 public:
  37     /**
  38        Add a new weak reference.
  39
  40        The implementation keeps the amount of memory consumed linear in the
  41        number of living references added, not linear in the number of total
  42        references added.
  43
  44        @param e
  45        a non-null reference.
  46     */
  47     void add(com::sun::star::uno::Reference< T > const & e) {
  48         OSL_ASSERT(e.is());
  49         for (typename WeakReferenceList::iterator i(m_list.begin()); i != m_list.end();) {
  50             if (com::sun::star::uno::Reference< T >(*i).is()) {
  51                 ++i;
  52             } else {
  53                 i = m_list.erase(i);
  54             }
  55         }
  56         m_list.push_back(com::sun::star::uno::WeakReference< T >(e));
  57     }
  58
  59     /**
  60        Remove a living reference.
  61
  62        @return
  63        a living reference, or null if there are none.
  64     */
  65     com::sun::star::uno::Reference< T > remove() {
  66         while (!m_list.empty()) {
  67             com::sun::star::uno::Reference< T > r(m_list.front());
  68             m_list.pop_front();
  69             if (r.is()) {
  70                 return r;
  71             }
  72         }
  73         return com::sun::star::uno::Reference< T >();
  74     }
  75
  76 private:
  77     typedef std::list< com::sun::star::uno::WeakReference< T > > WeakReferenceList;
  78
  79     WeakReferenceList m_list;
  80 };
  81
  82 }
  83
  84 #endif
  85
  86 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */