[Java] Java继承的实现与继承限制分析

public class extendsdemo01 {
  static class person{
  private int age;
  private string name;
  public int getage() {
    return age;
  }
  public void setage(int age) {
    this.age = age;
  }
  public string getname() {
    return name;
  }
  public void setname(string name) {
    this.name = name;
  }
  public void tell(){
    system.out.println("姓名: "+getname()+" 年龄:"+getage());
  }
  }
  static class student extends person{
  private int score;
  public int getscore() {
    return score;
  }
  public void setscore(int score) {
    this.score = score;
  }
  public void say(){
    system.out.println("成绩:"+getscore());
  }
  }
  public static void main(string [] args){
  student s=new student();
  s.setage(20);
  s.setname("张三");
  s.setscore(100);
  s.tell();
  s.say();
  }
}

姓名: 张三  年龄:20
成绩:100

public class extendsdemo02 {
  static class people{
  private int age;
  public int getage() {
    return age;
  }
  public void setage(int age) {
    this.age = age;
  }
  }
  static class worker extends people{
  public void tell(){
    system.out.println(getage());
  }
  }
  static class petworker extends worker{
  }
  public static void main(string [] args){
  worker worker=new worker();
  worker.setage(100);
  worker.tell();
  }
}

100