Pass by value or reference

[Manoj]

HI. I am a C++ programmer mingrating to Java



I have this query..Does Java support pass by value or pass by reference.

Following code suggests that Java supports Pass by reference as it calls the "callme " function from the derieved

class. But then it calls the constructor of the base class also which suggests that it makes a copy of base class...It

means its pass by value..

Please help


class Base {

Base(){

System.out.println("I am in base class constructor ");

}

void callme(){

System.out.println("I am in base class");

}



}

class Derieved extends Base {

void callme(){

System.out.println("I am in derieved class");

}

}


class dispatch {

public static void main(String args[]) {

Derieved dd = new Derieved() ;

fff(dd);

}

}



static void fff(Base bb){

bb.callme();

}

}




OUTPUT is

I am in base class constuctor

I am in base derieved class

[Zafir Anjum]

Java (almost) always uses pass by reference. The only time it uses pass by

value is for int, boolean, char etc. Note that in Java all access to an object

is through its reference.


The first line of output you get is when the Derived class is constructed. As in

C++, the subclass construction continues only after the base class portion gets

constructed.


The second line of output of course is from the callme() of the Derived class.

[vinjava]

Mr. Manoj

the out put is
I am in base class constructor
"I am in base class"

b'coz u r calling the method of the base class using it's object obviously the result is as above and the constructor is calls by default when ever u create ad nobject of the class



vinay kumar s.v