如何初始化静态变量

public class MyClass {
    private static int myStaticVar = 10;
}

public class MyClass {
    private static int myStaticVar;

    static {
        myStaticVar = 10;
    }
}

public class MyClass {
    private static int myStaticVar;

    public static void initStaticVar() {
        myStaticVar = 10;
    }
}