Don Raab

Java Champion. Creator of the Eclipse Collections OSS Java library. Inspired by Smalltalk. Opinions are my own.

Stable, Secure, and Affordable Java

Azul Platform Core is the #1 Oracle Java alternative, offering OpenJDK support for more versions (including Java 6 & 7) and more configurations for the greatest business value and lowest TCO.

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What do you know about the code changes that were just introduced into the codebase? When will you notice if something goes wrong?

Jakarta EE 11: Beyond the Era of Java EE

This user guide provides a brief history of Java EE/Jakarta EE and a detailed overview of some of the specifications that will be updated in Jakarta EE 11.

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Immutable Collections in Java with Sealed Types

JDK 15 was released on September 15, 2020. JEP 360 Sealed Types was included as a preview feature in this release, with its second preview in JDK 16. Sealed Types is part of Project Amber. Sealed classes or interfaces can be used to restrict the interfaces or classes that are allowed to extend them. Also learn about the source code for an experimental implementation of a collections framework can be found in the Deck of Cards Kata repo.

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Don Raab

Sealed Classes

Tutorials

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If you want to know what I spoke about in @jcon_conference in Germany, here's an interview I did at the @foojayio podcast:

#Java #JCON #JakartaEE #AI #A2A

02:06 PM · May 04, 2026

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