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Presentation: Records and Sealed Types - Coming Soon to a JVM Near You!

Track: Evolving Java

Location: Windsor, 5th flr.

Duration: 10:35am - 11:25am

Day of week: Wednesday

Slides: Download Slides

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OpenJDK's Project Amber has been delivering small improvements for a while now. With the release of Java 14, a group of major new features starts to arrive.

The first is Records - a new syntax for declaring a class that "just holds data" and fills the same role that tuples do in other programming languages. Coming soon are Sealed Types, which fundamentally change Java's model of object oriented programming by providing a middle way between classes that are final and classes that are completely open for extension. These seemingly unrelated ideas are not only powerful in their own right but are actually connected at a deep level. They light the way for further upcoming features, such as Pattern Matching (no, not regular expressions) and much, much more. Our journey will take in other recent changes in the Java language and will show how big ideas in language design sometimes start from surprisingly small implementation details.

Speaker: Ben Evans

Java Champion, Author of "Java in a Nutshell"

Ben Evans is Principal Engineer and Architect for JVM technologies at
New Relic. Prior to joining New Relic, Ben co-founded jClarity
(acquired by Microsoft) and was Chief Architect (Listed Derivatives)
at Deutsche Bank.

Ben is the author of 5 books - "The Well-Grounded Java Developer",
"Java: The Legend", "Optimizing Java" and the recent editions of "Java
in a Nutshell". He is the track lead for Java / JVM at,
writes regularly for industry publications and is a frequent speaker
at technical conferences worldwide.

Ben has been active in Free and Open Source Software for over 20
years, co-founded the AdoptOpenJDK initiative (with Martijn Verburg),
and served on the JCP Executive Committee for 6 years.

Find Ben Evans at

2020 Tracks

  • Monday, 8 March

  • Tuesday, 9 March

  • Wednesday, 10 March