Practice Hashset (15.3.2.1) - Collections and Generics

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9 questions

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6 sample questions

Question 1.
What is the primary purpose of a HashSet in Java?
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Think about how sets work in mathematics.
Question 2.
Name one method used to add an element to a HashSet.
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Consider the name of the method that suggests adding items.
3Question 3.
What is the primary characteristic of a HashSet?
- Maintains order
- Allows duplicates
- Stores unique elements
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Think about how a typical set behaves.
4Question 4.
True or False: The order of elements in a HashSet is guaranteed.
- True
- False
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Recall what unordered means.
Question 5.
You are tasked with creating a contact manager that should not allow duplicate contacts. How would you utilize HashSet in your solution? Write a sample code snippet demonstrating how you would add and check contact names.
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Consider how you would check for duplicates before adding.
Question 6.
Explain how you'd handle equality in HashSet's elements to prevent collisions effectively. What key methods must be overridden?
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Think about the rules for comparison in programming.

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