How to overload << operator in nested class - c++

Question

I have three classes: Client Database and Node as a nested class in Database.
Data of a Node is a pointer to a Client object, the Client class has it's own overloaded << operator.
I need to have an overloaded << operator that will output all of the linked list's data.
The problem that I encounter is not being able to iterate through all of the list using the << overloaded operator, the best thing that I can do is to output the head node's data using getData member, for some reason Node::Print won't output all of the lists Client *data.
Here is the Database class and two of the mentioned methods << and print().
Databse.h
class Databse
{
private:
class Node //node as nested class
{
public:
Node();
void setNode(Client*&);
Node* nextNode(Node*&);
Client getData();
void print (Node*);
private:
Client* data; //holds pointer to Client object
Node* next; //holds pointer to next node in list
};
Node *head; //holds the head node
int nClients;
public:
Databse();
friend ostream& operator<<(ostream&, const Databse&);
Node* getHead() const;
~Databsey();
};
Databse.cpp relevant methods:
ostream& operator<<(ostream& out, const Databse& obj)
{
out << endl << "The databse holds" << obj.nClients << " clients:" << endl;
out << obj.head->getData();
obj.head->print(obj.getHead());
return out;
}
void Database::Node::print (Node* str)
{
Node* current = str ;
while (current->next)
{
cout << current->data;
current = current->next;
}
}
Thanks.

Answer 1

Another approach.
Keep Database::Node:print() very simple -- print the data on the object only.
Let ostream& operator<<(ostream& out, const Database& obj) take care of iterating over the nodes in the list and print each node.
Here's the updated code.
class Database
{
private:
class Node //node as nested class
{
public:
Node();
void setNode(Client*&);
Node* nextNode(Node*&);
// Need this to allow iteration of the list of nodes
// of a Database object.
Node* nextNode() const
{
return next;
}
Client getData();
// Print the data associated with just one node.
void print(ostream& out) const
{
cout << data;
}
private:
Client* data; //holds pointer to Client object
Node* next; //holds pointer to next node in list
};
Node *head; //holds the head node
int nClients;
public:
Database();
friend ostream& operator<<(ostream&, const Database&);
Node* getHead() const;
~Database();
};
ostream& operator<<(ostream& out, const Database& obj)
{
out << endl << "The databse holds" << obj.nClients << " clients:" << endl;
// Iterate over the nodes of the Database object
// and print each one.
Database::Node* current = obj.head;
for ( ; current != NULL; current = current->nextNode() )
{
current->print(out);
// Printing a whitespace between nodes makes the
// output more readable.
out << " ";
}
return out;
}

Answer 2

Just add the overloaded operator<< as you would with any other class, for instance:
class Databse
{
private:
class Node //node as nested class
{
public:
Node();
void setNode(Client*&);
Node* nextNode(Node*&);
Client getData();
friend ostream& operator<<( ostream&, const Node*& pNode );
private:
Client* data; //holds pointer to Client object
Node* next; //holds pointer to next node in list
};
Node *head; //holds the head node
int nClients;
public:
Databse();
friend ostream& operator<<(ostream&, const Databse&);
friend ostream& operator<<( ostream&, const Node*& pNode );
Node* getHead() const;
~Databsey();
};
And then implement it as follows:
ostream& operator<<( ostream& out, const std::add_lvalue_reference<Databse::Node*>::type pNode )
{
Databse::Node* pCurrNode = pNode;
while( pCurrNode )
{
std::cout << pCurrNode->data;
pCurrNode = pCurrNode->next;
}
return out;
}

Answer 3

fix print that accept ostream
ostream& Database::Node::print (ostream& out, Node* str)
{
Node* current = str ;
while (current) //bugfix
{
out << current->data;
current = current->next;
}
return out
}
and then you can call
ostream& operator<<(ostream& out, const Databse& obj)
{
out << endl << "The databse holds" << obj.nClients << " clients:" << endl;
out << obj.head->getData();
obj.head->print(out,obj.getHead());
return out;
}