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WeAreDevelopers LIVE • Sep 21, 2022

Route from Java to Kotlin

Christian Woerz

Ditch verbose Java boilerplate and Lombok dependencies forever. See how Kotlin’s native null safety and extension functions instantly upgrade your JVM development workflow.

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#1 about 4 min

Introduction to Kotlin and Java interoperability

Overview of Kotlin's multi-paradigm nature and seamless integration with existing Java libraries.

#2 about 2 min

Understanding file extensions and top-level functions

Writing concise Kotlin scripts without wrapping functions inside classes.

#3 about 4 min

Variable types, type inference, and string templates

Using mutable and immutable variables along with string interpolation and multi-line strings.

#4 about 3 min

Using control flow statements as assignment expressions

Assigning the return values of if statements and try-catch blocks directly to variables.

#5 about 4 min

Pattern matching with the when expression

Replacing Java's switch statements with exhaustive pattern matching and type checking.

#6 about 7 min

Function formatting with named and default arguments

Creating concise functions using expression bodies and omitting overloaded methods through default parameters.

#7 about 3 min

Overriding loops with ranges and stepping

Iterating using numeric ranges, exclusive bounds, and reversed sequences.

#8 about 3 min

Immutable lists and destructuring index values

Instantiating collections and splitting index-value pairs directly in loop declarations.

#9 about 9 min

Implementing strong null safety and optional checks

Migrating from Java optionals to explicit nullable types for safely handling absent values.

#10 about 6 min

Writing lambdas and processing lists functionally

Filtering collections using trailing lambdas without relying on heavy stream chains.

#11 about 4 min

Enhancing existing types using extension functions

Adding new methods to final classes and Java types natively without inheritance.

#12 about 5 min

Data classes, custom properties, and operator overloading

Generating boilerplate utility methods alongside customized property accessors and mathematical overrides.

#13 about 11 min

Audience questions on scalability and language features

Inquiries exploring string manipulation techniques, Scala similarities, learning resources, and operator overloading risks.

Matching moments

3:03 min

Introduction to Kotlin history and Java ecosystem interoperability

Urs Peter · WWC 2022

1:33 min

Configuring runtime Java and Kotlin interoperability protocols

Iris Hunkeler · LIVE

4:52 min

Introduction to the Java and Kotlin ecosystems

Iris Hunkeler · LIVE

1:43 min

Summarizing the practical engineering advantages of writing Kotlin

Iris Hunkeler · LIVE

2:50 min

Kotlin language features and null safety

Iris Hunkeler · LIVE

2:18 min

Recommended resources and frameworks for learning Kotlin natively

Iris Hunkeler · LIVE

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