package com.oop.demo01;public class Demo02 {public static void main(String[] args) {//静态方法 staticStudent.say1();//非静态方法Student student = new Student();student.say2();}public void a1(){b1();}public void b1(){a1();}public static void a2(){b2();}public static void b2(){a2();}public static void a3(){//b3();    报错}public  void b3(){a3();}}

package com.oop.demo01;//学生类
public class Student {//方法public static void say1(){System.out.println("学生说话了");}//方法public void say2(){System.out.println("学生说话了");}
}

package com.oop.demo01;public class Demo03 {public static void main(String[] args) {int add = Demo03.add(1,2);System.out.println(add);}public static int add(int a, int b){return a+b;}
}

package com.oop.demo01;//值传递
public class Demo04 {public static void main(String[] args) {int a =1;System.out.println(a);Demo04.change(a);System.out.println(a);}//返回值为空private static void change(int a) {a = 10;}
}

package com.oop.demo01;//引用传递：对象，本质还是值传递
public class Demo05 {public static void main(String[] args) {Person person = new Person();person.name = "123";System.out.println(person.name);   //123person.change(person);System.out.println(person.name);   //epfox}
}//定义了一个Person类，有一个属性：name
class Person{String name;public void change(Person person){person.name = "epfox";}
}