Concurrency & Multithreading
Threads, locks, the memory model and thread pools — the topic most senior Java interviews live or die on.
- 1✓
Walk me through the Java thread lifecycle. What is the difference between BLOCKED and WAITING?
senior🎬 animated - 2✓
What is a race condition? Why is counter++ broken under concurrency, and what are your options to fix it?
senior🎬 animated - 3✓
What does volatile actually guarantee? Explain visibility and happens-before in the Java Memory Model.
staff🎬 animated - 4✓
Compare synchronized, ReentrantLock and ReadWriteLock. How do you decide which to use, and how do you avoid deadlock?
senior - 5✓
How do you size and configure a thread pool for a production service? Explain ExecutorService internals.
architect