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¸Õ¸Õ¿´µ½Ò»ÆªÎÄÕÂÌá³öc++¶à̬Óëjava¶à̬²»Í¬µÄµØ·½£¬»ù±¾Òâ˼ÈçÏ£º
Çë¿´C++´úÂ룺
class Base
{
public:
Base()
{
init();
}
virtual ~Base() {}
protected:
int value;
virtual void init()
{
value = 100;
}
};
class Derived : public Base
{
public:
Derived()
{
init();
}
protected:
void init()
{
cout << "value = " << value << endl;
// ×öһЩ¶îÍâµÄ³õʼ»¯¹¤×÷
}
};
int main(int argc, char* argv[])
{
Base* pb;
pb = new Derived();
delete pb;
return 0;
}
Ö´Ðнá¹ûÊÇ
value = 100
ÔÙ¿´java´úÂ룺
class Base
{
public Base()
{
init();
}
protected int value;
protected void init()
{
value = 100;
}
}
class Derived extends Base
{
public Derived()
{
init();
}
protected void init()
{
System.out.println("value = " + value);
// ×öһЩ¶îÍâµÄ³õʼ»¯¹¤×÷
}
}
public class Test
{
public static void main(String[] args)
{
Base base = new Derived();
}
}
Ö´Ðнá¹ûÊÇ
value = 0
value = 0
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import java.util.ArrayList;
import java.util.HashMap;
public class Client {
/**
* @param args
*/
public static void main(String[] args) {
test1();
System.out.println("==================================");
test2();
......