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/****************************************************************************************
**
* @file     weakPtr.cc

* @brief    

  @example  

* @author   classfellow@qq.com
* @date     2013-10 
* @updated  2014-10-21 
* @warning
* @license  BSD
**           
****************************************************************************************/

#ifdef _WIN32
#include <windows.h>
#else
#include <assert.h>
#endif
#include "macros.h"
#include "ref_counted.h"
#include "WrapperObj.h"
#include "WeakPtr.h"

namespace base {

  WeakReference::Flag::~Flag() {
  }

  WeakReference::WeakReference() {
  }

  WeakReference::WeakReference(const Flag* flag) : flag_(flag) {
  }

  WeakReference::~WeakReference() {
  }

  bool WeakReference::is_valid() const { return flag_.get() && flag_->IsValid(); }

  WeakReferenceOwner::WeakReferenceOwner() {
  }

  WeakReferenceOwner::~WeakReferenceOwner() {
    Invalidate();
  }

  WeakReference WeakReferenceOwner::GetRef() const {
    // If we hold the last reference to the Flag then create a new one.
    if (!HasRefs())
      flag_ = new WeakReference::Flag();

    return WeakReference(flag_.get());
  }

  void WeakReferenceOwner::Invalidate() {
    if (flag_.get()) {
      flag_->Invalidate();
      flag_ = NULL;
    }
  }

} //end namespace base