java 类的继承

public class Animal { 
    private String name;  
    private int id; 
    public Animal(String myName, int myid) { 
        name = myName; 
        id = myid;
    } 
    public void eat(){ 
        System.out.println(name+"正在吃"); 
    }
    public void sleep(){
        System.out.println(name+"正在睡");
    }
    public void introduction() { 
        System.out.println("大家好！我是"         + id + "号" + name + "."); 
    } 
}

public class Penguin extends Animal { 
    public Penguin(String myName, int myid) { 
        super(myName, myid); 
    } 
}


public class Mouse extends Animal { 
    public Mouse(String myName, int myid) { 
        super(myName, myid); 
    } 
}

参考：

https://www.runoob.com/java/java-inheritance.html