//定义人员类 class Person { private String name;//姓名   private int age;//性别   private String address;//住址   public Person(){}   public Person(String name,int age)   {   this.name=name;   this.age=age;   }   public Person(String name,int age,String address)   {                  (   ①   )//调用本类的构造方法   this.address=address;   }   //省略setter和getter }