Thread: Passing by reference in Java?

I have a pretty complicated program in which I need to pass by reference. But it seems I can't.

Rather than post the entire code of my complicated program, I wrote a much simpler program with the same exact problem.

I want to change the value of the Character object in the function "changechObj7" but it won't change. I keep getting the output 'P' both times.

How do I fix this? It's so easy in C++.....

import java.util.Scanner;
 
public class Play
{
        public static void main(String[] args)
        {
                Play play = new Play();
 
                play.dance();
        }
 
        public void dance()
        {
                Character chObj7 = new Character('P');
                System.out.println(chObj7);
                changechObj7(chObj7);
                System.out.println(chObj7);
 
        }
 
        public void changechObj7(Character chObj7)
        {
                chObj7 = 'K';
        }
}

I know that the character object is a reference to an address that holds the value "P".

So, in my "changechObj7" function, I pass the ADDRESS location that holds "P".

I change what the address holds by setting it equal to 'K'.

I don't change the address, I change the value the address holds. Shouldn't that be a permanent change?

This does not work this way in java. All you do in your changechObj7 method is to reassign a value to your parameter variable.
You can still achieve what you want in java, but you have to approach it a little bit differently.
The fastest and simplest way is to cheat a little and use a one-element char array instead. Then you can change the value at position 0 at the array.
A cleaner solution would be to define a new class which has a character as public attribute. If you pass an instance of that class you can simply change the value of the attribute.