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Topic 5: Lambda Expressions & Functional Programming

Mastering Java's functional programming paradigm — lambda expressions, functional interfaces, method references, and convenience methods.

Topic Structure

Document Purpose Status
Part 1 — Lambda Fundamentals Lambda syntax, functional interfaces, Consumer/Predicate/Function/Supplier Complete
Part 2 — Method References & Chaining Method references, chaining with andThen/compose, Comparator convenience Complete
Book Reading Effective Java insights (Items 42–44) Complete
Summary Combined final understanding Complete

What You'll Master

  • Lambda Expressions — Syntax, closures, effectively final variables, deferred execution
  • Functional Interfaces — @FunctionalInterface, SAM contract, custom interfaces
  • Built-In Interfaces — Consumer, Predicate, Function, Supplier (and Bi/Unary/Binary variants)
  • Method References — Static, bounded receiver, unbounded receiver, constructor
  • Chaining — andThen, compose, and, or, negate
  • Comparator Convenience — comparing, thenComparing, reversed

Section Coverage

Section Lectures Part
14. Mastering Java Lambdas Expressions, Interfaces, and Method References 1–8 Part 1
14. Mastering Java Lambdas Expressions, Interfaces, and Method References 9–13 Part 2

Resources

Primary Course

Book Reference

  • Effective Java by Joshua Bloch — Items 42–44 (Lambdas & Functional Interfaces)

Key Internals to Understand

  • How lambdas are compiled (invokedynamic bytecode instruction)
  • Why effectively final is required (deferred execution)
  • Bounded vs unbounded receiver semantics
  • Comparator helper method chaining

Progress Tracker

  • Complete Tim's course Section 14 on Lambdas & Method References
  • Write Part 1 topic notes (Lambda fundamentals)
  • Write Part 2 topic notes (Method references & chaining)
  • Read Effective Java Items 42–44
  • Complete book reading notes
  • Synthesize final summary

Start Date: 2026-03-12 | Target Completion: