Textual order of static variables and initialization order in Java

I only spend five minutes to find a duplicate in SO.

My question is simple. Does the following code always work?

public class LexicalOrderStatic {
    private static Integer a1 = initA1();

    private static Integer a2 = initA2();


    private static Integer initA2(){
        return new Integer(5) / a1;
    }

    private static Integer initA1(){
        return new Integer(5);
    }

    public Integer getA1(){
        return new Integer(a2);
    }

    public static void main(String[] args) {
        LexicalOrderStatic lexLuthor = new LexicalOrderStatic();
        System.out.println(lexLuthor.getA1());

    }
}

In java can I be sure that a1 is always initialized before a2 ?

Thanks. Dw is ok if it is asked or if it is very simple.