Java vs C++(五) 构造器中调用虚函数

java: 行为正确，表现多态

package com.cisco.test;




class Child extends Base{
public void init(){
System.out.println("child init");
}
}


public class Base {


public Base() {
init();
}


public void init(){
System.out.println("base init");
}


public static void main(String[] args){
new Child();
}


}

child init

/*
* Child.cpp
*
* Created on: Oct 23, 2013
* Author: jiafu
*/


#include "Child.h"
#include <iostream>


namespace std {


Child::Child() {
// TODO Auto-generated constructor stub


}


void Child::init(){
cout<<"child init"<<endl;
}


Child::~Child() {
// TODO Auto-generated destructor stub
}


} /* namespace std */

c++:

/*
* Child.h
*
* Created on: Oct 23, 2013
* Author: jiafu
*/


#ifndef CHILD_H_
#define CHILD_H_


#include "Base.h"


namespace std {


class Child: public std::Base {
public:
Child();
virtual ~Child();
virtual void init();
};


} /* namespace std */
#endif /* CHILD_H_ */

/*
* Base.h
*
* Created on: Oct 23, 2013
* Author: jiafu
*/


#ifndef BASE_H_
#define BASE_H_


namespace std {


class Base {
public:
Base();
virtual void init();
virtual ~Base();
};


}
#endif

/*
* Base.cpp
*
* Created on: Oct 23, 2013
* Author: jiafu
*/


#include "Base.h"
#include <iostream>


namespace std {


Base::Base() {
Base::init();
}


Base::~Base() {
}


void Base::init(){
cout<<"base init"<<endl;
}


} /* namespace std */

调用：

Child child;
Base& b1=child;
b1.init();


Base* b2=new Child;
b2->init();

构造时不表现多态，调用方法时表现了。