add a static variable and a non static variable together in java

Question

Can we add a static variable and a non static variable together in java? For example,

class Evolve{
    static int i = 1;
    static int j = 2;
    int x = 3;
    static int y = 6;

    public static void main(String args[]){
        System.out.println(i + j);
        System.out.println(x + i);
        System.out.println(i + y);
        System.out.println(x + j);
    }
}

Thanks

Answer 1

Not until you initialize an instance of Evolve and refer to it as

this.i

or like this

Evolve evolve = new Evolve();
System.out.println(evolve.i + Evolve.j);

Answer 2

不， 非静态 （或instance ）变量x在main方法的静态上下文中不可访问。

Answer 3

您需要将非静态对象置于实例中，然后可以使用Evolve.i + this.x添加它们

Answer 4

There is nothing to do with static/non-static about whether you can add it or not.

It is simply how you should access static and non-static (instance) variable.

Answer 5

Since x is an instance variable, you need an instance of the Evolve object...

public static void main(String args[]){
  Evolve ev = new Evolve();
  System.out.println(Evolve.i + Evolve.j);
  System.out.println(ev.x + Evolve.i);
  System.out.println(Evolve.i + Evolve.y);
  System.out.println(ev.x + Evolve.j);
}

Answer 6

您可以将静态变量加在一起，但要添加带有静态变量的非静态变量，则必须使用this。（“ non-static variable”），但静态方法除外。