现有: class A {public String name="a"} class B extends A {public String name="b"} 执行如下代码后的结果是哪项?() A a=new B(); System.out.println(a.name);
A: a
B: b
C: 编译失败
D: 运行时抛出异常
A: a
B: b
C: 编译失败
D: 运行时抛出异常
举一反三
- 阅读程序,下面的哪个选项是正确的?( )。 class ExSuper{ String name; String nick_name; public ExSuper(String s,String t) { name = s; nick_name = t; } public String toString(){ return name; } } public class Example extends ExSuper{ public Example(String s,String t){ super(s,t); } public String toString(){ return name +"a.k.a"+nick_name; } public static void main(String args[]){ ExSuper a = new ExSuper(“First”,“1st”); ExSuper b = new Example(“Second”,“2nd”); System.out.println(“a is”+a.toString()); System.out.println("b is"+b.toString()); } }
- 下列程序的运行结果是( )class Demo{private String name;Demo(String name){this.name = name;}private static void show(){System.out.println(name)}public static void main(String[] args){Demo d = new Demo(“lisa”);d.show();}}
- 以下代码执行后的结果是: public class Person { String name = “小芳”; public Person(String name) { name = “小兰”; } public void show() { this.name = “小翠”; } public static void main(String[] args) { Person p = new Person(“小凤”); System.out.print(p.name); p.show(); System.out.print(p.name); } }
- (06-06)分析如下所示的Java代码,其中this关键字的意思是( )。 public class Test { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; //this关键字所在的行 } } Class Main{ Public static void main(String []args){ Test T1 = new Test(); T1.setname(“zhangsan”); } }
- 【填空题】public class ThisTest{ private String name; private int age; public ThisTest() { System.out.println("产生一个新的Person对象。"); } public ThisTest (String name, int age) { this(); this.name = name; this.age = age; } public String getInf() { return "姓名:" + name + ",年龄:" + age; } public static void main(String[] args) { ThisTest per = new ThisTest("张三", 20); System.out.println(per.getInf()); } } 运行结果为:____