Java认证模考试题(七)

来源:java认证发布时间:2012-11-12 12:47:33java认证视频

Question: 38


The Person, Student and Teacher are class names. These classes have the following inheritance relation as shown below:

Person

|

---------------

| |

Student Teacher

There is the following expression in a Java source file:

Person p = new Teacher();

Which of the following expressions return true?


A. p instanceof Teacher

B. p instanceof Student

C. p instanceof Person

D. None of them returns true

Explanation:


The instanceof operator is used to test the type of an object. Because the reference p refers to a Teacher object and the Teacher is a subclass of the Person class the expressions in answer A and C will return true.

Correct Answer: A,C 38 of 60

 

上一页12下一页

视频学习

我考网版权与免责声明

① 凡本网注明稿件来源为"原创"的所有文字、图片和音视频稿件,版权均属本网所有。任何媒体、网站或个人转载、链接转贴或以其他方式复制发表时必须注明"稿件来源:我考网",违者本网将依法追究责任;

② 本网部分稿件来源于网络,任何单位或个人认为我考网发布的内容可能涉嫌侵犯其合法权益,应该及时向我考网书面反馈,并提供身份证明、权属证明及详细侵权情况证明,我考网在收到上述法律文件后,将会尽快移除被控侵权内容。

最近更新

社区交流

考试问答