The Art of Java Type Patterns

on YouTube ↗46m

" summary

Covers concrete language changes: pattern matching for instanceof (preview in JDK 14, final in JDK 16) removes redundant casts and uses flow scoping; pattern matching for switch (JEP 406 in JDK 17) adds null labels, guarded cases, dominance and completeness checks and shifts to a when guard in upcoming JDK 19 (JEP 427); records (JDK 14) enable record deconstruction patterns and composition with var and proposed array patterns; sealed classes (JDK 15) make exhaustive switches practical. Code examples show compiling rules and where the compiler rejects unreachable cases.

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" chapters (27)

1. 0:00Intro
2. 0:30Modern Java
3. 3:17Pattern Matching Fundamentals
4. 4:20Pattern Types
5. 6:12Switch Expressions
6. 7:34Switch Statement
7. 8:18Switch Expression (JDK 12)
8. 10:10Simple Java Data Class
9. 11:53Records (JDK 14)
10. 12:19Records Additional Details
11. 13:47Java Inheritance
12. 14:23Sealed Classes (JEP 360)
13. 16:16Using The instanceof Operator
14. 17:24Pattern Matching For instanceof (JDK 14)
15. 20:30Flow Scoping For Binding Variables Scope of local variable runs from its declaration until the end of the block in which it is dedared
16. 23:06Pattern Matching For instanceof Puzzler
17. 24:23JDK 18 jshell
18. 29:57Pattern Matching for switch (Completeness)
19. 31:19Guarded Patterns (JDK 18)
20. 33:10Guarded Patterns (JDK 19)
21. 33:29Pattern Dominance
22. 36:38Pattern Matching instanceof And Records
23. 37:24Pattern Matching For Records (JEP 405)
24. 38:17Patterns Are Composable
25. 40:08Patterns And Local Variable Type Inference
26. 41:57Pattern Matching For Arrays
27. 44:01Azul Zulu Builds of OpenJDK • Enhanced build of Open source code

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