Calling a Java method with no name

I'm looking at the code below and found something a bit strange:

public class Sequence {
    Sequence() {
        System.out.print("c ");
    }

    {
        System.out.print("y ");
    }

    public static void main(String[] args) {
        new Sequence().go();
    }

    void go() {
        System.out.print("g ");
    }

    static {
        System.out.print("x ");
    }
}

I would've expected this to give a compilation error as the System.out with "y " doesn't belong to a method declaration just a { }. Why is this valid? I don't see how this code would or should be called.

When running this it produces x y c g also, why does the static { } get called before the sequence constructor?