SPRING BOOT AND KOTLIN, A MATCH MADE IN HEAVEN@NICOLAS_FRANKEL

@nicolas_frankel #kotlin #springboot 3

WHY SPRING BOOT?

@nicolas_frankel #kotlin #springboot 4

Convention over configuration

• Kickstart a project in minutes, not days

Out-of-the-box features

•Actuator

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KOTLIN

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Open Source

Compiles to

• JVM bytecode

• JavaScript

•Native (experimental)

A "simpler Scala"

@nicolas_frankel #kotlin #springboot

KOTLIN MAIN FEATURES

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Functional and object-oriented

Statically typed

Null safety

No checked exceptions

Named & optional arguments

Lambdas

Extension functions more later

Java compatibility

(And more...)

@nicolas_frankel #kotlin #springboot

KOTLIN MAIN BENEFITS

@nicolas_frankel #kotlin #springboot 9

More expressive than Java

Improved OO

Functional too

HELLO KOTLIN!

package hello // no semicolons

// namespace-level functions

// types on the right

// no special syntax for arrays

// optional return type

fun main(args: Array<String>) {

println("Hello Kotlin!")

}

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THE KILLER FEATURE: EXTENSIONS

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Extension methods

Extension properties

EXTENSION METHOD

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Add new methods on an existing type

Called like a method on the type

Translated to static Utilmethod in the bytecode

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ENOUGH TALK…

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SPRING WEB 5 FUNCTIONAL & KOTLIN

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https://docs.spring.io/spring/docs/current/spring-framework-reference/languages.html#kotlin-bean-definition-dsl

REACTIVE SPRING

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KEY TAKEAWAY

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Q&A

@nicolas_frankel #kotlin #springboot

http://blog.frankel.ch/

@nicolas_frankel

@nfrankel (#vjug24)

https://git.io/vVSLG

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