What design to choose to initialize complex objects?

Question

Let's say that I have a class that encapsulates one (or several) members (s) that needs to be initialized in some way, and there is no sensible way to use the class without it (so I don't want to make it optional), Is it better initialization run in its constructor like this:

class MyClass
{
    MyClass()
    {
        if(!obj.initialize()
            throw ...;
    }

private:
    MyObject obj;
}

or you suggest the following design:

class MyClass
{
    MyClass()
    {
    }

    bool initialize()
    {
        return obj.initialize();
    }

private:
    MyObject obj;
}

The first one looks attractive, because I can guarantee that all the requirements for using my class are met after the constructor starts, and I can report any errors by throwing an exception.

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Answer 1

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std::fstream fs; // initialized but not configured

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std::fstream fs("myfile.txt", std::ios::in); // initialized & configured

Answer 2

MyObject::initialize MyObject ( throw). MyClass .