class Base{ private String name = "base"; Base(){ tellName(); printName(name); } public void tellName(){ System.out.println("tell "+ name); } public void printName(String name){ System.out.println("print "+ name); } } class Drived extends Base{ private String name = "Drived"; Drived(){ tellName(); printName(name); } public void tellName(){ System.out.println("tell "+ name); } public void printName(String name){ System.out.println("print "+ name); } } public class TestObject { public static void main(String args[]){ new Drived(); } } 结果为: tell null print base tell Drived print Drived