Practice Visibility (20.2.2) - Java Memory Model and Thread Safety - Advance Programming In Java

Practice: Visibility

Lesson 20.2.2Java Memory Model and Thread Safety

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9 questions

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6 sample questions

Question 1.
What Java keyword ensures that changes to a variable are visible across multiple threads?
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Think of a keyword that starts with 'v'.
Question 2.
What is the main problem if a variable is not declared volatile in a multithreading context?
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Consider what happens when threads work with copies of data.
3Question 3.
What does the volatile keyword guarantee in Java?
- It prevents all memory leaks
- It makes a variable accessible to all threads
- It ensures visibility of changes across threads
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Think of what happens when a variable is marked as volatile.
4Question 4.
True or False: Using synchronized methods can affect the visibility of instance variables.
- True
- False
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Consider how locks work in synchronization.
Question 5.
Consider a multithreaded application where a boolean global variable controls a thread's execution. Design a simple code snippet that demonstrates both visibility issues and fixes using volatile.
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Reflect on how the variable interacts with multiple threads.
Question 6.
Write a scenario involving two threads that demonstrate a race condition due to improper visibility practices and suggest a solution.
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Think about how simultaneous access could lead to errors.

5 more questions in this section. Enroll free to practise them all.