Java认证模考试题（六）

Question: 35
A. public class test {

public int x = 0;

public test(int x)

{

this.x = x;

}

}

B. public class Test{

public int x=0;

public Test(int x) {

this.x = x;

}

}

C. public class Test extends T1, T2 {

public int x = 0;

public Test (int x) {

this.x = x;

}

}

D. public class Test extends T1{

public int x=0;

public Test(int x){

this.x = x;

}

}

E. protected class Test extends T2{

public int x=0;

public Test(int x){

this.x=x;

}

}

Explanation:

In the Test.java source file the class name should be Test, not test, for it is case-sensitive in Java. One class should have not more than one superclass. The protected modifier can not be put in front of the class.

Correct Answer: B,D 35 of 60 |||

Question: 36

Person

|

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

| |

Student Teacher

There is the following expression in a Java source file:

Person p = new Student();

Which one of the following statements are true?

B. The expression is illegal.

C. Some errors will occur when compile.

D. Compile is correct but it will be wrong when running.

Explanation: 

Correct Answer: A 36 of 60

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

Person

|

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

| |

Student Teacher

In Java source file a specific method has an argument. In order to handle all these classes in this method which type of argument of this method should be used?

B. Student

C. Teacher

D. Object

E. None of them can be used.

Explanation: 

Correct Answer: A,D 37 of 60