Java5.5

package bbb;

public class Instrument {
   public void play(){
      System.out.println("弹奏乐器");
      }
}
 class Wind extends Instrument{
       public void play(){
           System.out.println("弹奏Wind");
       }
       public void play2(){
           System.out.println("调用Wind的play2");
       }
 }
 class Brass extends Instrument{
     public void play(){
         System.out.println("弹奏Brass");
     }
         public void play2(){
               System.out.println("调用Brass的play2");
     }
 }

package bbb;

public class Music {
  public static void tune(Instrument i) 
  {  i.play();}
   
  public static void main(String[] args) {
      Instrument a=new Instrument();
         Wind b=new Wind();
         Brass c=new Brass();
   tune(a);
  tune(b);
  tune(c);
    }
  
}

 class Monkey {
       public void speak(){
            System.out.println("咿咿呀呀...");
       }
   
}
 class People extends Monkey{

    People(String s) {
        
        // TODO 自动生成的构造函数存根
    }
         public People() {
        // TODO 自动生成的构造函数存根
    }
        {
        // TODO 自动生成的构造函数存根
    }
        public void speak(){
            System.out.println("小样不错嘛会说话了！");
        }
           void think(){
            System.out.println("别说话，认真思考！");
            }
            
    }

    public class E{
        public static void main(String[] args) {
            People a=new People();
            People b=new People();
            a.speak();
            b.think();
        }
    }