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
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