Ten Common mistakes made in Functional Java
summary
Ten concrete Java pitfalls with fixes and code patterns: avoid large block lambdas — extract named methods; stop returning Streams as reusable data; never rely on peek for side effects or mutate shared objects in map — return new immutable copies; replace repeated forEach stages with a single pipeline to speed batch jobs; order operations correctly (distinct vs limit) and avoid accidental infinite streams; use Optional APIs (map, ifPresent, orElseGet) instead of isPresent/orElse side effects; handle checked exceptions in lambdas by lifting to Either or using Vavr Try.
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chapters (18)
- 0:00Intro
- 2:27Introduction
- 5:48Doing too much in a single lambda
- 8:57Returning a stream
- 14:34Mutable objects
- 15:05Functional programming
- 16:23Mutable data
- 17:16State changes
- 22:50What is functional programming
- 25:56Order of operations
- 27:19Unit test
- 33:57If Statement
- 45:36Exception
- 46:01Block lambdas
- 47:46Checked exceptions
- 50:56The eater type
- 52:01The lift type
- 53:36The pair type
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