Java Questions

Q:

X implements Y, Z

Arguments:

1. X should be class
2. Y, Z should be interfaces

A) Only 1 is true B) Only 2 is true
C) Both 1 and 2 are true D) None
 
Answer & Explanation Answer: C) Both 1 and 2 are true

Explanation:

Both the statements are true 

Report Error

View Answer Report Error Discuss

Filed Under: Java - Technology
Job Role: IT Trainer

0 13202
Q:

Which of the following statements are equal for a variable declared in the interface ?

1. int X=10
2. public int X=10
3. public static final int X=10

A) Only 1 and 2 are equal B) Only 2 and 3 are equal
C) All are unequal D) All are equal
 
Answer & Explanation Answer: D) All are equal

Explanation:

All the statements are equal because inside an interface a variable declared will be public static final by default 

Report Error

View Answer Report Error Discuss

Filed Under: Java - Technology
Job Role: IT Trainer

0 13152
Q:

What are the types of Collision Resolution Techniques and the methods used in each of the type?

Answer

Open addressing (closed hashing),


The methods used include: Overflow block,


 Closed addressing (open hashing)


The methods used include: Linked list, Binary tree…

Report Error

View answer Workspace Report Error Discuss

Subject: Java - Technology

16 12924
Q:

public abstract class Shape {

private int x;

private int y;

public abstract void draw();

public void setAnchor(int x, int y) {

this.x = x;

this.y = y;

}

}

Which two classes use the Shape class correctly?

A) public class Circle implements Shape { private int radius; B) public abstract class Circle extends Shape { private int radius; }
C) public class Circle extends Shape { private int radius; public void draw(); D) None
 
Answer & Explanation Answer: B) public abstract class Circle extends Shape { private int radius; }

Explanation:

Only B is true

Report Error

View Answer Report Error Discuss

Filed Under: Java - Technology

0 12842
Q:

How are this() and super() used with constructors?

Answer

Constructors use this to refer to another constructor in the same class with a different parameter list.


Constructors use super to invoke the superclass's constructor. If a constructor uses super, it must use it in the first line; otherwise, the compiler will complain.

Report Error

View answer Workspace Report Error Discuss

Subject: Java - Technology

1 11453
Q:

Which two method you need to implement for key Object in HashMap ?

Answer

In order to use any object as Key in HashMap, it must implements equals and hashcode method in Java.

Report Error

View answer Workspace Report Error Discuss

8 8867
Q:

Which method names follow the JavaBeans standard?

A) addSize B) putDimensions
C) getCust D) deleteRep
 
Answer & Explanation Answer: C) getCust

Explanation:

C use the valid prefixes 'get' and 'is

Report Error

View Answer Report Error Discuss

Filed Under: Java - Technology

0 8662
Q:

If you are using C language to implement the heterogeneous linked list, what pointer type will you use?

Answer

The heterogeneous linked list contains different data types in its nodes and we need a link, pointer to connect them. It is not possible to use ordinary pointers for this. So we go for void pointer. Void pointer is capable of storing pointer to any type as it is a generic pointer type.

Report Error

View answer Workspace Report Error Discuss

Subject: Java - Technology

1 8255