Question

Not exactly sure how to phrase this, sorry for ambiguous title.
Anyways, here’s basically my cuestión.

Basically, I know how I can pass values into the class using the contructor and functions and such, like,

class bob {
    int value;
    public bob(int x) {
        value = x;
    }
}

bob test = bob(5);

But how do you handle things like operators and such? Like, if a person added the classes together:

bob test1 = bob(5), test2 = bob(3), test3 = test1 + test2;

How could I make it actually do something is a person tried to add the two instantiated objects together?

Or if I said something like,

bob test = 5;

How could I do something with a value you initialize it to have?

Answer 1

You can’t do either in Java. Java’s operators only work for primitive types (and String as a special exception), and regular objects can only be initialized with compatible objects or null.

Instead, you should define appropriate methods and constructors:

public bob add(bob other) { ... }

then use

bob test1 = new bob(5);
bob test2 = new bob(3);
bob test3 = test1.add(test2);

Since you can’t do bob test = 5;, just do bob test = new bob(5);.