Java Functional Programming Idioms

on YouTube ↗56m

" summary

Shows concrete Java 8 idioms: express a prime check with IntStream.range + noneMatch instead of loops, build readable pipelines by aligning stream operations vertically (filter → map → forEach) and rely on the runtime to fuse operations rather than merging calls for micro‑optimisation, prefer method reference for pass‑through lambdas, treat lambdas as glue (no multi‑line lambdas), and keep lambdas pure — avoid shared mutable state (the array trick defeats laziness and breaks correctness).

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" chapters (12)

1. 0:00Introduction to idioms
2. 2:51Functional programming basics
3. 7:25Thinking functionally
4. 12:26Functional pipeline pattern
5. 16:47Vertical alignment of operations
6. 23:43Performance and lazy evaluation
7. 27:59Finding best functions
8. 30:24Lambda as glue code
9. 38:57Method references
10. 43:15Readable lambda parameters
11. 47:05Pure functions in Java
12. 55:15Summary and closing

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