Quiz on Java Collection

Which of these packages contain all the collection classes?

• java.lang

• java.util

• java.net

• java.awt

Which of these classes is not part of Java’s collection framework?

• Maps

• Array

• Stack

• Queue

Which of this interface is not a part of Java’s collection framework?

• List

• Set

• SortedMap

• SortedList

Which of these methods deletes all the elements from invoking collection?

• clear()

• reset()

• delete()

• refresh()

What is Collection in Java?

• A group of objects

• A group of classes

• A group of interfaces

• None of the mentioned
  

What will be the output of the following Java program?

1. import java.util.*;

2. class Array

3. {

4. public static void main(String args[])

5. {

6. int array[] = new int [5];

7. for (int i = 5; i > 0; i--)

8. array[5-i] = i;

9. Arrays.fill(array, 1, 4, 8);

10. for (int i = 0; i < 5 ; i++)

11. System.out.print(array[i]);

12. }

13. }

• 12885

• 12845

• 58881

• 54881

What will be the output of the following Java program?

1. import java.util.*;

2. class Bitset

3. {

4. public static void main(String args[])

5. {

6. BitSet obj = new BitSet(5);

7. for (int i = 0; i < 5; ++i)

8. obj.set(i);

9. obj.clear(2);

10. System.out.print(obj);

11. }

12. }

• {0, 1, 3, 4}

• {0, 1, 2, 4}

• {0, 1, 2, 3, 4}

• {0, 0, 0, 3, 4}

Which of these return type of hasNext() method of an iterator?

• Integer

• Double

• Boolean

• Collections Object

Which of these methods is used to obtain an iterator to the start of collection?

• start()

• begin()

• iteratorSet()

• iterator()

Which of these methods can be used to move to next element in a collection?

• next()

• move()

• shuffle()

• hasNext()