c++ classes and object reference

Question

I have the following c++ class

class Object 
{
    public:
        Object(parameters);
 ...
        const Object& method1(parameters) const;
        Object& method2(parameters) const;

    private:
}

the method1 and method2 implementations are:

const Object& Object::method1(parameters) const 
{
...
    Object* _obj = new Object;
...
    return *_obj;
}

Object& Object::method2(parameters) const 
{
...
    Object* _obj = new Object;
...
    return *_obj;
}

I have not defined a copy constructor. I know the functions return a reference to the allocated object and I still have to use "delete" to delete it. I would like to avoid wasting memory and preserve information hiding.

Is this the right way to do this, or am I missing something?

Answer 1

This is bad as nothing will ever delete the objects. They will be leaked.

Return smart pointers, a copy of the object without newing it, or the raw pointer.

Answer 2

It depends on the class, but returning a reference to a dynamically allocated object is probably not a good idea.

• If the class has value semantics (supports copy and assignment), you should return an actual object; dynamic allocation of objects with value semantics should be avoided.

• If the class is a full fledged entity object, whose lifetime is managed by the application, you should probably return a raw pointer.

• If the returned object still needs more processing before it will be managed by the application, you should probably return std::auto_ptr, or if you can use C++11, std::unique_ptr; the caller will then release it once the application logic takes over, and if anything happens in the meantime, the object will automatically be destructed and the memory freed.