下列程序段中，正确的是______。①class MvClass { int var = 100; static int getVar() { return var; } }②public class MyClass { final int date; void MyClass (int d) { date = d; } }③public class MyMain { public static void main(String args[]) { System.out.println(Myclass1.date); } } class MyClass1 { int data = 10; }④class IamAbstract { final int f; double d; abstrct void method(); }