Static ? static ? static ?

Question

i wish to use the main() function to see my results step by step. but, do i really have to make every method a static one in order to elimate the error message " can't make static reference to method test2() in class testdrive" ? is there a better way ? what does static modifier really do anyway ? what's the use of it ? examples ?
thank you very much !
code =>
public class testdrive {
public static void main(String args[])
System.out.println(test());
static int test()
int a;
a=1 + test2();
return a;
int test2()
int a;
a=2;
return a;

Answer 1

methods or variables declared as static meaning there's only one such copy for the class, even if you initialize objects from the particular class, the method, variable will also be shared between the instances. You can call a static method without an instance of a class, example I have a class Dog with a public static method bark, I can simply call it using:
Dog.bark();
rather than
Dog dog = new Dog();
dog.bark();
Both ways will work, but its better to perform it in the 1st way to show its a static method.
As for static variable, it shares among the instances, there's only 1 copy. For example, in a Counter class, I have a static variable int count.
Counter counter1 = new Counter();
counter1.setCount(2);
System.out.println(counter1.getCount());
This will return you 2.
However, if you intialize another instance:
Counter counter2 = new Counter();
System.out.println(counter2.getCounter());
This will also return you 2.
Correct me if I'm wrong