Back to the CompletableFuture: Concurrency in Action

on YouTube ↗55m

" summary

Explains why plain Future fails (blocking get, no chaining, awkward exception handling) and shows concrete tools to stop using raw Threads: use ThreadLocal for per-thread SimpleDateFormat, AtomicLong for lock‑free counters, ConcurrentHashMap plus putIfAbsent for safe caches, and ExecutorService thread pools (single, cached, fixed, scheduled, work‑stealing). Demonstrates CompletableFuture features: supplyAsync with custom executor, thenCompose for flat mapping, thenCombine for merging results, allOf/anyOf and exceptionally/handle, plus complete/timeout control.

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" chapters (38)

1. 0:00Intro
2. 1:37Goals
3. 2:33Motivation
4. 4:54Thread Safety
5. 6:24Concurrency & Sharks
6. 7:11Agenda Single Threading
7. 9:56Programming by Coincidence
8. 10:40Design by Contract
9. 11:19Temporal Coupling
10. 12:05Multithreading Forms Concurrent Form
11. 12:26Form: Concurrency Multiple Tasks
12. 14:53Form: Parallelism Fire & Forget
13. 15:46Form: Asynchrony
14. 16:38Runnable No Input
15. 17:13Thread Runnable Based
16. 18:19ThreadLocal Resource Confinement
17. 19:36Atomic Operations Compound
18. 21:29Thread Safe Collections Compound Operations
19. 23:16Promises in JavaScript
20. 23:48Callback Hell in JavaScript Verbose
21. 26:18Future Completed in the Future
22. 27:23Executor Framework Thread Management
23. 28:16Thread Pool Thread Management
24. 28:46Executor Factories
25. 30:25Executor Service
26. 31:31Blocking Result Retrievar Blocking Get
27. 31:59Futures Chaining No Workflows
28. 32:47Futures Combination Blocking InvokeAny
29. 33:25Exception Handling Multiple Exceptions
30. 34:07CompletableFuture Transformation
31. 34:46Blocking Operations
32. 35:00Transformation/Chaining Workflows
33. 36:17Tasks Composition
34. 38:00Controllable Futures
35. 39:03Multiple Futures Control
36. 40:06Tasks Combination Collect Results
37. 41:49Embrace Concurrency
38. 42:15Embrace Review Your Concurrency Application

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