src/base/scoped_nsobject.h

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// scoped_nsobject supports RAII for Objective-C objects.
// The idea and code of scoped_nsobject originally comes from
// chromium base/scoped_nsobject.h.
// See http://src.chromium.org/viewvc/chrome/trunk/src/base/scoped_nsobject.h?revision=29399

#ifndef MOZC_BASE_SCOPED_NSOBJECT_H_
#define MOZC_BASE_SCOPED_NSOBJECT_H_

#import <Foundation/Foundation.h>

#include "base/port.h"

template<typename NST>
class scoped_nsobject {
 public:
  typedef NST* element_type;

  explicit scoped_nsobject(NST* object = nil)
      : object_(object) {
  }

  ~scoped_nsobject() {
    [object_ release];
  }

  void reset(NST* object = nil) {
    // We intentionally do not check that object != object_ as the caller must
    // already have an ownership claim over whatever it gives to scoped_nsobject
    // and scoped_cftyperef, whether it's in the constructor or in a call to
    // reset().  In either case, it relinquishes that claim and the scoper
    // assumes it.
    [object_ release];
    object_ = object;
  }

  bool operator==(NST* that) const {
    return object_ == that;
  }

  bool operator!=(NST* that) const {
    return object_ != that;
  }

  operator NST*() const {
    return object_;
  }

  NST* get() const {
    return object_;
  }

  void swap(scoped_nsobject& that) {
    NST* temp = that.object_;
    that.object_ = object_;
    object_ = temp;
  }

  // scoped_nsobject<>::release() is like scoped_ptr<>::release.  It is NOT
  // a wrapper for [object_ release].  To force a scoped_nsobject<> object to
  // call [object_ release], use scoped_nsobject<>::reset().
  NST* release() {
    NST* temp = object_;
    object_ = nil;
    return temp;
  }

 private:
  NST* object_;

  DISALLOW_COPY_AND_ASSIGN(scoped_nsobject);
};


#endif  // MOZC_BASE_SCOPED_NSOBJECT_H_