Functional Java Workshop

Workshop Overview

Saran Ahluwalia

https://github.com/ahlusar1989/java-workshop-materials

https://ahlusar1989.github.io/java-workshop-materials/

About Me

AE Intern in Compozed
Previously worked at Social Tables, DivvyCloud and the Wynyard Group
Currently studying mathematics and statistics
Marathoner

How this Workshop Came to Be

First language I learned were Scala and Haskell
Java 8 Study Group in DC and Durham
"Clean Code" Book
Working on research in optimizing reinforcement learning algorithms
These experiences have changed the way I think about writing code.

Plan for the Workshop

Some thoughts about Functional Programming
Immutability Review and Exercises
Lambda Review
Streams Review and Exercises
Optionals Review
Multi-step guided exercise - Green Field
Function Composition Review
Multi-step guided exercise - Refactoring
Coda: Advanced Immutability

We will focus on practical applications - very few vocabulary words and mathematical jargon!

Functional Programming Hype

Solves all your concurrency problems!
The solution to Moore's Law slowing down!
Super Trendy! Big Money!
Retro/Vintage/Hipster Programming - Lisp is Cool Again!

But seriously, how many people in this room...

have major concurrency problems?
have a Moore's Law problem?

Why Are We Here?

I want to be a functional programmer!

Wrong answer

I want to be a better programmer!

This is why we're here...

What is clean code?

Meaningful Names
Small Methods
Small Classes
TDD
SOLID Principles

Functional practices urge us towards clean code

What is Functional Programming?

Functions as first class citizens?
Pure functions?
Lambdas?
Closures?
Recursion with Tail Call Optimization?
Lazy streams?
Immutability?
Declarative vs. Imperative?
Monads (Haskell)?
Code as Data (Lisp)?

Argh!

No one can define it!

Except maybe Uncle Bob...

Spoiler alert...Immutability is the Key!

Next Steps

Demo and overview of the source repo
Setup Exercise: Make sure you can run the tests in whatever IDE you choose