java代码块 学习

class Student {            static {                System.out.println("Student 静态代码块");            }            {                System.out.println("Student 构造代码块");            }            public Student() {                System.out.println("Student 构造方法");            }        }        class Demo2_Student {            static {                System.out.println("Demo2_Student静态代码块");            }            public static void main(String[] args) {                System.out.println("我是main方法");                Student s1 = new Student();                Student s2 = new Student();            }        }