C is equivalent to Java’s TOSTRING?

class A {
public:
 int i;
};

std::ostream& operator<<(std::ostream &strm, const A &a) {
 return strm << "A(" << ai << ")";
}

A x = ...;
std::cout << x << std::endl;

class A {
private:
 friend std::ostream& operator<<(std::ostream&, const A&);
 int j;
 };

std::ostream& operator<<(std::ostream &strm, const A &a) {
 return strm << "A(" << aj << ")"; 
}

I want to control the content written to the stream, i.e. cout, to obtain objects of a custom class. Is this possible in C? In Java, you can override the toString() method for similar purposes.

In C, you can overload the operator<

class A {
public:
 int i;
};

std::ostream& operator<<(std: :ostream &strm, const A &a) {
 return strm << "A(" << ai << ")";
}

So you can output on the stream Examples of classes:

A x = ...;
std::cout << x << std::endl;

If your operator << wants to print out the inside of class A, and really needs to access its private and protected members, you can also declare it as a friend function:

class A {< br />private:
 friend std::ostream& operator<<(std::ostream&, const A&);
 int j;
};

std: :ostream& operator<<(std::ostream &strm, const A &a) {
 return strm << "A(" << aj << ")";
}