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Sven Woltmann
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stream gatherers
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Stream Gatherers – Write Your Own Stream Operations!

Sven WoltmannSven WoltmannDecember 6, 2023
Find out what a stream gatherer is and how you can use it to implement any intermediate stream operations.
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statements before super(...)
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Flexible Constructor Bodies in Java: Executing Code Before super()

Sven WoltmannSven WoltmannDecember 5, 2023
As of Java 22, you can finally execute code in constructors before calling super(...) or this(...). This article shows you how.
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string templates java
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String Templates in Java

Sven WoltmannSven WoltmannDecember 5, 2023
Learn how String Templates in Java simplify the composition of strings from text, variables and calculated values.
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unnamed variables and patterns
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Unnamed Variables and Patterns in Java

Sven WoltmannSven WoltmannDecember 4, 2023
Variables & patterns that we have to define but do not need can be designated with '_'. Find out what you need to bear in mind.
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Hexagonal Architecture with Quarkus
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Hexagonal Architecture With Quarkus
[Tutorial]

Sven WoltmannSven WoltmannOctober 30, 2023
In the fourth part of the series on hexagonal architecture, we migrate the existing application to a Quarkus application... without changing a line of code in the application core.
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ports and adapters feature image
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Ports and Adapters Java Tutorial: Adding a Database Adapter

Sven WoltmannSven WoltmannOctober 4, 2023
In the third part of the series on hexagonal architecture, we extend the application with a JPA adapter that stores the data in a MySQL database.
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hexagonal architecture java
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Hexagonal Architecture with Java – Tutorial

Sven WoltmannSven WoltmannJuly 4, 2023
In this article, I will show you step by step how to implement a Java application with hexagonal architecture – and how to enforce compliance with the architectural rules using Maven and the library “ArchUnit”.
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structured concurrency java
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Structured Concurrency in Java with StructuredTaskScope

Sven WoltmannSven WoltmannJune 14, 2023
What is Structured Concurrency and why do we need it? How does StructuredTaskScope work? What is the advantage of Structured Concurrency?
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java 21 features
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Java 21 Features
(with Examples)

Sven WoltmannSven WoltmannJune 8, 2023
The new Java 21 features with examples: Virtual Threads, Sequenced Collections, Record Patterns, Pattern Matching for switch; new preview features: String Templates, Unnamed Patterns and Variables, Unnamed Classes and Instance Main Methods ... and more!
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how to switch java versions in windows
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How to Change Java Versions in Windows
(updated for Java 25)

Sven WoltmannSven WoltmannMarch 21, 2023
In this article, I'll show you how to install several Java versions simultaneously in Windows and how to switch between them on the command line with short commands.
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