Practice Collectors - 4.7.1 | 4. Java Collections Framework (Advanced | Advance Programming In Java
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Collectors

4.7.1 - Collectors

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Practice Questions

Test your understanding with targeted questions

Question 1 Easy

What method would you use to collect elements into a list from a stream?

💡 Hint: Think about the method that gathers all elements.

Question 2 Easy

What is the purpose of the .filter() method in a stream?

💡 Hint: What do you need to do to exclude data?

4 more questions available

Interactive Quizzes

Quick quizzes to reinforce your learning

Question 1

What method do you use to filter elements in a stream?

filter()
map()
collect()

💡 Hint: Recall how to narrow down a stream.

Question 2

True or False: Collectors can only be used to gather data into lists.

True
False

💡 Hint: What types of collections can you think of?

1 more question available

Challenge Problems

Push your limits with advanced challenges

Challenge 1 Hard

You have a list of names. Write a method that uses streams to filter out names starting with vowels and then group them by their length.

💡 Hint: Identify the starting character and think about length classification.

Challenge 2 Hard

Create a Stream that collects all unique ages from a list of people, filtering out duplicates and returning them in a sorted order.

💡 Hint: Focus on distinct() to remove duplicates and sorted() for ordering.

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