testbird.java

所学课程的编码。java的基础例子。可以练习java通过这些例子。。

/*
 * David Java File Created on 2006-10-7
 * 
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 */
package chap04;

abstract class Bird {
    String food = "grain";
    abstract void fly();
    protected void eat(){
        System.out.println("eat " + food);  
    }
}

class BLBird extends Bird {
    String food = "leaf";
    public void fly() {
        System.out.println("BLBird fly");
    }
    public void eat(){
 	   System.out.println("eat " + food); 
    }
    
    
    public String eat(String a){
	   System.out.println("eat " + a); 
	   return a;
    }
   
    void bite(){
        System.out.println("bite " + food);  
    }
    public void sing(){
        System.out.println("BLBird sing a song");
    }
    public String sing(String name){
        System.out.println("BLBird sing a song:"+name);
        return name;
    }
}

public class TestBird {

    public static void main(String[] args) {
        BLBird aBird = new BLBird();
        aBird.fly();
        //aBird.eat();
        //aBird.eat("aaa");
        //aBird.bite();
        //aBird.sing();
        //aBird.sing("JHT");
        
    }
    protected  void aa(){
    	System.out.println("Test protected method.");
    }
}