方法的重写

1、在子类中可以根据需要对从基类中继承的方法进行重写

2、重写方法必须和被重写方法具有相同对的方法名称,相同的参数列表和返回值类型

3、重写方法不能使用比被重写方法更严格的访问权限

在方法重写的时候注意:对那个方法进行重写尽量copy那个方法,如果在重写

getInfo这个方法时,不小心写成了GetInfo当编译的时候,不会报错,但是得不到你想要的结果

例如:

class Person {
    private String name;
    private int age;
    public void setName(String name){this.name=name;}
    public void setAge(int age) {this.age=age;}
    public String getName(){return name;}
    public int getAge(){return age;}
    public String getInfo() {
          return "Name: "+ name + "\n" +"age: "+ age;
  }
}

class Student extends Person {
    private String school;
    public String getSchool() {return school;}
    public void setSchool(String school)
    {this.school =school;}
    public String getInfo() {
      return  "Name: "+ getName() + "\nage: "+ getAge() 
                    + "\nschool: "+ school;
		}
}

public class TestOverWrite {
public static void main(String arg[]){
        Student student = new Student();
        Person person = new Person();
        person.setName("none");
        person.setAge(1000);
        student.setName("John");    
        student.setAge(18);
        student.setSchool("SCH");
        System.out.println(person.getInfo());
        System.out.println(student.getInfo());
    }
}

  

posted @ 2018-12-24 16:27  雪地里的Alan  阅读(98)  评论(0编辑  收藏