Java MCQ - Collections Framework


Mock java test, multiple-choice questions with answers on collections framework for self-assessment and evaluation. Java self-evaluation test for OCJP aspirants.



Java self-evaluation test

Topic- Collections framework in Java

The test consists of 13 questions.

No negative marking for this test.

No Time limit

The pass percentage is 70%

The correct answer with a description will be displayed after the answer has been marked.

Submit the test to calculate your score once you are done with all the questions.

Complexity Level- Medium





Q1: Select all the core collection interfaces


























Q2: Select all the concrete classes that implement Set interface
















Q3: Select all the correct statements about HashSet and LinkedHashSet


















Q4: Select all the implementing classes of the List interface


















Q5: Lists are collections that maintain elements in order

Select True or False











Q6: The List is a collection that contains only unique elements

Select True or False











Q7: Select all the implementing classes of the Map interface

















Q8: A Map can contain duplicate keys

Select True or False











Q9: The changes made to the returned SortedSet by a headset(object toElement) method are reflected in the original SortedSet

Select True or False










Q10: Select the classes which have a comparator() method

















Q11: Select the correct methods that can be called on objects implementing the Map interface

















Q12: Select the correct output of the execution of the below program:

public static void main(String[] args) {
SortedSet ss=new TreeSet();
ss.add("a");
ss.add("b");
ss.add("c");
ss.add("d");
ss.add("e");
ss.add("f");
ss.add("g");
SortedSet ss2=ss.headSet("e");
Iterator ssitr2=ss2.iterator();
while(ssitr2.hasNext())
{
System.out.println(ssitr2.next().toString());
}
}
















Q13: Select the correct output of the execution of the below program:

public static void main(String[] args) {
SortedSet ss=new TreeSet();
ss.add("a");
ss.add("b");
ss.add("c");
ss.add("d");
ss.add("e");
ss.add("f");
ss.add("g");
SortedSet ss2=ss.tailSet("e");
Iterator ssitr2=ss2.iterator();
while(ssitr2.hasNext())
{
System.out.println(ssitr2.next().toString());
}
}