programming

14 Oct 2026

DZone Java Zone

Going All In On the JVM 25 Virtual Threads

The project AngularAndSpring has been refactored from Spring Reactor to Spring blocking APIs using JDK 25 and virtual threads.

The Old Architecture

The reason AngularAndSpring was built using Spring Reactor was primarily the efficient use of operating system threads and memory under high load. Spring Reactor had a limited thread pool (usually the number of available CPU cores) and used OS threads only when the CPU had work to do. It did not let the operating system threads sleep. This used CPU resources much better and required far fewer OS threads, each of which needs around a megabyte of memory.

14 Oct 2026 6:00pm GMT

13 Oct 2026

DZone Java Zone

"Works on My Machine" Is an Architecture Problem

The familiar claim that software behaves correctly on a developer workstation but fails elsewhere is often treated as a debugging cliché. In practice, it describes an architectural failure where part of the system's behavior exists outside version control. Source code may be identical while the effective execution environment differs in runtime version, CPU architecture, filesystem semantics, locale, time zone, native libraries, certificates, environment variables, dependency resolution, or build tooling. When those inputs remain implicit, the developer workstation becomes an undocumented dependency. The resulting failure is not merely environmental inconvenience, but it is evidence that the system lacks a complete, reproducible definition of the conditions under which it is expected to build and run. Reproducible-build practices are based on the same principle: a declared source and build inputs should create an independently verifiable path to the resulting artifact rather than depending on hidden machine state.

The Machine Is an Input, Even When the Repository Pretends Otherwise

A repository normally captures application source, configuration templates, and dependency manifests, but operating assumptions often remain outside it. A service compiled with one JDK can behave differently under another. Code that relies on the host time zone inherits machine configuration, and Java's default time zone is derived from the environment in which the JVM runs; APIs that obtain the system default can therefore return different values across hosts. Locale has a similar characteristic because a JVM maintains a default locale that can influence locale-sensitive operations.

13 Oct 2026 7:00pm GMT

12 Oct 2026

DZone Java Zone

Running TypeSafe AI's Jev Inside Neo4j for Confidence-Aware Sentiment Decisions

This is Part 3 of a series on running sentiment analysis inside Neo4j.

Part 1, Running Sentiment Analysis Inside Neo4j With a Java Plugin, used the VADER lexicon via a pure Java UDF - rule-based, fully local, high throughput.
Part 2, Wasm Inside Neo4j: Building the Example That Didn't Exist, embedded a Wasm runtime inside a Java UDF using wasmtime-java - sandboxed, still local, lower throughput.

Part 3 takes a different approach. Instead of bundling a scoring model inside the plugin JAR, we call TypeSafe AI's Jev from inside a Java UDF. Jev is a System One model - it doesn't generate text. It takes a state (the text to evaluate) and a set of typed questions and returns structured decisions with explicit probability and confidence information. No prompt engineering, no JSON schema coercion, no parsing.

12 Oct 2026 3:00pm GMT