4.1.1 - Collection Hierarchy Recap
Enroll to start learning
You’ve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take practice test.
Practice Questions
Test your understanding with targeted questions
What type of collection allows duplicates?
💡 Hint: Think about order and duplicates.
Name one implementation of Set.
💡 Hint: What prevents duplicates?
4 more questions available
Interactive Quizzes
Quick quizzes to reinforce your learning
Which collection type does not allow duplicates?
💡 Hint: Remember the characteristics of each type.
True or False: A TreeMap can contain null keys.
💡 Hint: Consider the sorting policy.
1 more question available
Challenge Problems
Push your limits with advanced challenges
Design a data structure using Java Collections that needs to prevent duplicates, maintain order, and allow quick access. Explain your choice.
💡 Hint: Think about the balance of characteristics between Sets and Lists.
Write a Java program that demonstrates the difference between a HashMap and a TreeMap with respect to their ordering and retrieval practices.
💡 Hint: Consider how data organization might affect retrieval time.
Get performance evaluation
Reference links
Supplementary resources to enhance your learning experience.