c**z
发帖数: 669 | 1 not sure where is wrong? Can someone help?
Thanks
class myclass
{
private:
myclass() {}
static myclass uniqueinstance;
static bool b;
public:
static myclass getinstance()
{
if(b==false)
{uniqueinstance=myclass();
b=true;
}
return uniqueinstance;
}
};
bool myclass::b=false;
void main()
{
myclass.getinstance();
} |
a********1
发帖数: 750 | 2 至少copy constructor 和assignment operator 也要private吧 |
P**********c
发帖数: 3417 | 3 re. 另外这个不thread safe。这种情况一般应该用double-checking lock.
【在 a********1 的大作中提到】
: 至少copy constructor 和assignment operator 也要private吧
|
r*******y
发帖数: 1081 | 4 it is not OK to return a copy of the object in the singleton pattern.
need to return a reference or a pointer
【在 c**z 的大作中提到】
: not sure where is wrong? Can someone help?
: Thanks
: class myclass
: {
: private:
: myclass() {}
: static myclass uniqueinstance;
: static bool b;
: public:
: static myclass getinstance()
|
l****l
发帖数: 8 | 5 myclass.getinstance(); => myclass::getinstance();
【在 c**z 的大作中提到】
: not sure where is wrong? Can someone help?
: Thanks
: class myclass
: {
: private:
: myclass() {}
: static myclass uniqueinstance;
: static bool b;
: public:
: static myclass getinstance()
|
r*********2
发帖数: 88 | 6 double check locking pattern. |
