class eddemo
{
    public static void main(String[] args)
    {
        son s=new son();
        System.out.println("主方法"+s.getname()+s.getage());
        son s1=new son("sisi",23);
    }
}
class father
{
    private String name;
    private int age;

    /*public father ()            //将父类的空参构造注释掉
    {
        System.out.println("父类的空参构造");
    }*/
    public father(String name,int age)
    {
        this.name=name;
        this.age=age;
                System.out.println("父类的有参构造");
        System.out.println(this.name+this.age);//输出父类的name和age
    }

    public void setname(String name)//setxxx和getxxx方法
    {
        this.name=name;
    }
    public String getname()
    {
        return name;
    }

    public void setage(int age)
    {
        this.age =age;
    }
    public int getage()
    {
        return age;
    }
}
class son extends father
{
     public son ()
    {
     super ("zhangsan",23);//调用父类的有参构造方法，对父类进行初始化，这样的话父类与子类
     System.out.println("子类的无参构造");//的初始化值不就一样了么？并且系统内存到底是产生了几                                                   //个对象，怎么运作的？
     }
     public son (String name,int age)
    {
      super (name,age);
     System.out.println("子类的有参构造");
     }

}

先生父类实例，后有子类对象