Question 1

Which of following methods is present in the Collection interface in Java?

hashCode()
hashNext()
Next()
AllRetain()
ensureCapacity()

Answer

Correct Option: A

Question 2

How many constructors are there for LinkedHashSet?

6
5
4
3
2

Answer

Correct Option: C

Question 3

Which of the following is not a subclass of RuntimeException?

IllegalArgumentException
NullPointerException
IOException
IndexOutOfBoundException
ArithmeticException

Answer

Correct Option: C

Question 4

What are the default values for initial capacity and load factor for HashSet?

Initial capacity : 12 Load factor : 0.75
Initial capacity : 14 Load factor : 0.75
Initial capacity : 16 Load factor : 0.75
Initial capacity : 16 Load factor : 0.65
Initial capacity : 12 Load factor : 0.65

Answer

Correct Option: C

Question 5

Which of the following methods is present in List interface?

subList(int startindex, int endindex)
previousIndex()
nextIndex()
hasPrevious()
hasMiddle()

Answer

Correct Option: A

Question 6

Which of the following methods is present in the vector class in Java?

trimToSize()
setElement(index,Element)
Seach()
Empty()
Remove()

Answer

Correct Option: A

Question 7

Which of the following statements is true for methods in queue in Java Collections?

Element() method retrieves and removes the head of the queue and returns Null if the queue is empty.
Element() method retrieves, but doesn’t remove the head of the queue and returns Null if the queue is empty.
Element() method retrieves and removes the head of the queue and throws exception if the queue is empty.
Element() method retrieves, but doesn’t remove the head of the queue and throws exception if the queue is empty.
Element() method removes the head of the queue and throws exception if the queue is empty.

Answer

Correct Option: D

Question 8

Which of the following statements is correct for the methods in queue in Java Collections?

Poll() method retrieves and removes the head of the queue or returns Null if the queue is empty.
Remove() method retrieves and removes the head of the queue or returns Null if the queue is empty.
Poll() method retrieves and removes the head of the queue or throws an exception if the queue is empty.
Remove() method retrieves and removes the head of the queue, but doesn’t return anything if the queue is empty.
Poll() method retrieves the head of the queue or returns Null if the queue is empty.

Answer

Correct Option: A

Question 9

Which of the following statements is correct for methods in the queue?

Peek() method retrieves and removes the head of the queue and returns Null if the queue is empty.
Peek() method retrieves and removes the head of the queue and returns nothing if the queue is empty.
Peek() method retrieves, but doesn’t remove the head of the queue and returns Null if the queue is empty.
Peek() method retrieves and removes the head of the queue and throws an exception if the queue is empty.
Peek() method retrieves, but doesn’t remove the head of the queue and throws an exception if the queue is empty.

Answer

Correct Option: C

Question 10

How many constructors are there of TreeSet class?

6
5
4
3
2

Answer

Correct Option: C

Question 11

How many constructors are there of HashSet?

6
5
4
3
2

Answer

Correct Option: C

Question 12

Which of the following methods is not present in the List interface?

indexOf(Element : e)
Setthere(index,element)
Get(index)
Remove(index)
Merge(c:collection,c1:collection)

Answer

Correct Option: E

Question 13

Which of the following methods is not necessary to define for a class if it implements the windowListener interface?

windowMoved()
windowClosing()
windowIconified()
windowActivated()
windowDeiconified()

Answer

Correct Option: A

Question 14

Which of the following methods is not present in the Java Collections interface?

retainAll(collection c)
toArray()
containsAll()
addAll(Collection c)
First()

Answer

Correct Option: E

Question 15

What will be the output of the above program?

Directions: Read the syntax given below and answer the question that follows.

public class If2 {
static boolean b1, b2;
public static void main(String [] args)
{
int x = 0;
if ( !b1 ) /* Line 7 */
{
if ( !b2 ) /* Line 9 */
{
b1 = true;
x++;
if ( 5 > 6 )
{
x++;
}
if ( !b1 ) x = x + 10;
else if ( b2 = true ) /* Line 19 */ x = x + 100;
else if ( b1 | b2 ) /* Line 21 */ x = x + 1000;
}
}
System.out.println(x);
}
}

0
1
101
111
110

Answer

Correct Option: C

Description: Question Based on Collections in Java
Number of Questions: 15
Created by: Amit Pandey
Tags: Question Based on Collections in Java Java Basics

Java Basics

Find more quizzes from top tags