Java - Cannot Find Symbol Error With Other Classes

Question

First and foremost I want to make myself clear: I am not asking what the cannot find symbol error means, I am simply asking what is causing this error in this context.

I have recently delved into classes in Java. Below is my first [non main] class:

class Test {
    public void test() {
        System.out.println("Hello, world!");
    }
}
class Main {
    public static void main(String[] args) {
        test();
    }
}

But I get the following error:

exit status 1
Main.java:8: error: cannot find symbol
                test();
                ^
  symbol:   method test()
  location: class Main
1 error

Can anyone please explain why this happens?

System.out.println("Thanks!");

Answer 1

The method test() is not declared static.

You are calling a non-static method test() in a static method main(). If you do not want to change the class Test you have to change main() as follow

public static void main(String[] args) {
    Test t = new Test();
    t.test();
}

If you do not want to change main() too much. Then you have to change the test() method as follow: public static void test() {}

and the inside the main() method:

Test.test()