My code works as I expected, but I want to ensure my logic is correct

I've written the following code to answer the request: Write an if statement that assigns 0 to x when y is equal to 20. My code works as I expected, but I want to ensure my logic is correct.

public class IfStatements
{

    public static void main(String[] args) 
    {

        int x, y = 20;

        if(y == 20)
            System.out.println("x = " + y);

    }

}