Java – Get and Set methods in another class

I’m learning java and I’m having trouble with the get and set methods in other classes.

My first class is named Department, and my second class is named Company. I want to set the number of employees in the class department and get the number of employees in the class company.

Department class

public class Department {

public int staffNumber;

public Department() {
    }

public void setStaffNumber(int staff) {
        this.staffNumber= staff;
    }

}

Company class

public class Company {

public Department staffNumber;

public Company() {
     }

public Department getStaffNumber() {
          return Department.staffNumber = Department.staffNumber;
     }

}

Can you please help me with the error message – Non-static variable staffNumber cannot be referenced from a static context?
Thanks

Here’s the problem:

return Department.staffNumber = Department.staffNumber;

The compiler reads Department.staffNumber as: staffNumber is a static variable in the Department class. This is your problem.

To solve this problem, you should only return instance data:

public Department getStaffNumber() {
    <Department attribute in the class>
    return staffNumber;
}

By the way, even if you have a Department.staffNumber static property in the Department class, it is recommended to return Department.staffNumber = Department.staffNumber; Doesn’t make any sense. It’s similar to this:

public class SomeClass {

int x;

public int getX() {
        return x = x; clumsy
        return x; now this might be better
    }
}