Asking about access modifiers in java!

Question

public class Program
{
public static void main(String[] args) {
//James
Worker worker1 = new Worker();
worker1.name = "James";
worker1.salary = 200000;

//Tom
Worker worker2 = new Worker();
worker2.name = "Tom";
worker2.salary = 150000;

System.out.println(CalculateTotalSalary(worker1.salary,worker2.salary));
}

//complete the function to calculate the total salary
static int CalculateTotalSalary(int a, int b){
int sum = a + b;
return sum;

}
}
class Worker{
String name;
int salary;
}

If static method cannot access to non-static variables why the //System.out.println(worker1.salary,worker2.salary)" works?

//I think worker1.salaray and and worker2.salary are non static variable.
Am I wrong , sir?

Answer 1

main() can access and use <worker1> and <worker2> because they are local variables.

That also mean main() can access and use members of `Worker` instances (<worker1> and <worker2>). For example the 'salary' member.

Except if the respective members were defined as private, in which case a getter/setter is usually employed for manipulating the private members' value.

So main can access <worker1>.salary and <worker2>.salary. Then when main() invokes CalculateTotalSalary() main() passes the two values as method arguments. CalculateTotalSalary() makes copies of them, sum them up, and return the result.

Answer 2

Ipang that's why they can be accessed into the "CalculateTotal" static method?

Answer 3

If you want to access non-static variables of a class in a static context then you need an object of that class and have access through that object. Thats the way to access non-static variables are accessed in static method..( you cannot access directly.. )

There you accessing salary by object worker1.
Simply 'salary' will error instead of worker1.salary

Hope it helps..

Answer 4

Ipang i see that but salary is not static variable , then
Why salary copies can act like statics variables

Answer 5

Ipang thanks a lot👌

Answer 6

Jayakrishna🇮🇳 thank you

Answer 7

<worker1> and <worker2> are local variables, they're accessible.

A static method cannot call non static methods. Also, a static method cannot access non static members (variables etc.) defined outside the static method itself.

If you defined <worker1> and/or <worker2> outside main(), they will not be accessible inside main() which is a static method. Here they are accessible cause they are defined locally.

Answer 8

The CalculateTotalSalary() only receives copies of <worker1> and <worker2> salary values.

main() can call CalculateTotalSalary() because both are defined as static methods ...