WeAreDevelopers Logo WeAreDevelopers
Sign in
For You LIVE
World Congress 2022 β€’ Jun 15, 2022

Moving from Java to Kotlin

Urs Peter

Tired of Java boilerplate and unpredictable null pointer exceptions? Discover how migrating to Kotlin can shrink your codebase by 40% while maintaining complete interoperability with existing tools.

Pause
Mute Enter Fullscreen
#1 about 4 min

Introduction to Kotlin history and Java ecosystem interoperability

How careful language design decisions enable seamless interoperability with the existing Java ecosystem.

#2 about 4 min

Condensing object-oriented boilerplate code with primary constructors

Combining field declarations and primary constructors reduces typical object-oriented boilerplate while maintaining instantiation safety.

#3 about 2 min

Simplifying functional programming capabilities with first-class functions

Treating functions as first-class citizens removes the necessity of managing cumbersome single-method functional interfaces.

#4 about 3 min

Implementing type-level null safety and smart casting

Enforcing strict nullability rules at the compiler level eliminates unexpected runtime exceptions during data operations.

#5 about 2 min

Eliminating utility classes by leveraging custom extension functions

Attaching custom operations to external classes directly eliminates the need for abstracted utility files.

#6 about 1 min

Creating expressive testing domain specific languages with infix functions

Using specialized syntax to omit standard calling conventions enables developers to construct readable unit test assertions.

#7 about 3 min

Working with immutable collections and data structure transformations

Default immutability paradigms and concise standard library transformations make data list processing robust and predictable.

#8 about 4 min

Simplifying asynchronous concurrency patterns safely with coroutines logic

Coroutines execute complex asynchronous procedures sequentially without requiring teams to rely heavily on dense reactive toolkits.

#9 about 3 min

Analyzing business benefits and return on investment metrics

Strategic developer education yields rapid returns on investment through significantly reduced defect rates and concise maintainability.

#10 about 6 min

Practical strategies for migrating an existing Java codebase

Converting standard application tests and domains sequentially ensures continuous operational functionality remains stable during syntax migration.

#11 about 2 min

Scaling idiomatic usage models and internal developer training

Establishing clear migration roadmaps and coaching prevents anti-patterns and encourages engineers to write truly idiomatic syntax.

Matching moments

3:01 min

Introduction to Kotlin and Java interoperability

Christian Woerz Β· LIVE

1:43 min

Summarizing the practical engineering advantages of writing Kotlin

Iris Hunkeler Β· LIVE

4:52 min

Introduction to the Java and Kotlin ecosystems

Iris Hunkeler Β· LIVE

1:33 min

Configuring runtime Java and Kotlin interoperability protocols

Iris Hunkeler Β· LIVE

2:18 min

Recommended resources and frameworks for learning Kotlin natively

Iris Hunkeler Β· LIVE

3:53 min

Key takeaways and future Kotlin Multiplatform improvements

Petar Marijanović · LIVE

More from World Congress 2022

What the heck do "declarative" and "reactive" actually mean? thumbnail
30:40
about 4 years ago

What the heck do "declarative" and "reactive" actually mean?

AndrΓ© Kovac

The Design and Evolution of C++ thumbnail
1:01:15
about 4 years ago

The Design and Evolution of C++

Bjarne Stroustrup

But, you're not Facebook thumbnail
31:12
about 4 years ago

But, you're not Facebook

Kristijan Ristovski

Communicate efficiently with Software Architecture Diagrams thumbnail
28:11
about 4 years ago

Communicate efficiently with Software Architecture Diagrams

Simon Lasselsberger

Get Ready for Jakarta EE 10! thumbnail
42:53
about 4 years ago

Get Ready for Jakarta EE 10!

Ivar Grimstad

Keep your code refactorable thumbnail
26:46
about 4 years ago

Keep your code refactorable

Gerrit Stapper

Upcoming sessions on this topic

Open session

World Congress 2026 North America

September 24, 2026 Β· 16:10–16:40

Outdoor Stage

When Humans Stop Writing Code: Rethinking Languages, Compilers, and Responsibility

Simon Auer

Organizer of flutter vienna meetup and CEO of marqably

Simon Auer
Open session

World Congress 2026 North America

September 25, 2026 Β· 11:00–11:30

Stage 7

Beyond Vibe Coding: An AI Builder’s Guide to Migrating 10k+ React Components

Shubham Chaurasia

Senior Software Engineer at Meta

Shubham Chaurasia
Open session

World Congress 2026 North America

September 25, 2026 Β· 09:40–10:10

Stage 3

Still on 4.8 or lower? A Practical Guide to Moving Your "Un-Migratable" .NET Apps

Isaac Levin

Developer Advocate

Isaac Levin
Open session

World Congress 2026 North America

September 24, 2026 Β· 14:50–15:20

Stage 9

How to generate business value through performance optimizations

Nikolai Sidiropulo

Software Engineer at Meta

Nikolai Sidiropulo
Open session

World Congress 2026 North America

September 24, 2026 Β· 16:50–17:20

Stage 3

Merging at Scale: From Broken Builds to Green Mainline

Manjari Akella, Preetam Dwivedi

Manjari Akella
Preetam Dwivedi
Open session

World Congress 2026 North America

September 24, 2026 Β· 17:30–18:00

Stage 7

Full Stack with Flutter - are we there yet?

Nemanja Stoőić

Senior Flutter Developer

Nemanja Stoőić

Related videos

Why Kotlin is the better Java and how you can start using it thumbnail
58:11
LIVE β€’ almost 3 years ago

Why Kotlin is the better Java and how you can start using it

Iris Hunkeler

Route from Java to Kotlin thumbnail
57:09
LIVE β€’ almost 4 years ago

Route from Java to Kotlin

Christian Woerz

Tackling Complexity With Functional Programming And Kotlin thumbnail
28:48
World Congress 2023 β€’ almost 3 years ago

Tackling Complexity With Functional Programming And Kotlin

Georg Dresler

Java Sealed Classes vs. Kotlin Sealed Classes #Slideless thumbnail
38:07
World Congress 2022 β€’ about 4 years ago

Java Sealed Classes vs. Kotlin Sealed Classes #Slideless

Lothar Schulz

Introducing Kotlin Multiplatform in an existing project thumbnail
47:37
LIVE β€’ almost 5 years ago

Introducing Kotlin Multiplatform in an existing project

Marco Gomiero

The Dark Corners of Kotlin Multiplatform thumbnail
29:09
World Congress 2026 Europe β€’ 2 months ago

The Dark Corners of Kotlin Multiplatform

Andrea Della Porta

Related articles

From learning to earning

Jobs that call for the skills explored in this talk.