c++ - 将默认值设置为单例

Question

我有使用gmock 框架进行测试覆盖的单例类。某些方法（例如示例中的 method1()）在调用期间会更改类的字段。有没有办法在不修改TestingClass的情况下为类的字段设置默认值？

例子：

class TestingClass
{

private:

TestingClass(): _field1(0)
              , _field2(0)
{

}
TestingClass(const TestingClass&){}
TestingClass & operator=(const TestingClass &){}

public:

static TestingClass Instance()
{
    static TestingClass instance;
    return instance;
}

void method1()
{
    _field1 = 777;
}
void method2()
{
    _field1 = 888;
}
void Show()
{
    std::cout << "\nField1 - " << _field1
              << "\nField2 - " << _field2
              << "\n";
}

//other methods...


private:

int _field1;
int _field2;

};