Passing by value means we pass a copy of the value.; Passing by reference means we pass the real reference to the variable in memory.; Java object references are passed by value. All object ...

When the code is first executed, we will enter the main() method and initialize number to the value of 10.; We will then output the value of number before calling the change() method.; In the change() ...

So if we tried to change the reference variable like d = new demo(30); the variable remains unaffected. Thus it is proved that we can't change the referece variable, we can use the reference or ...