# Java Advent

Published articles for Java Advent.

This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles.

## Using Ahead-of-Time Cache Optimizations in Recent JDK Releases

DevFeed: [Using Ahead-of-Time Cache Optimizations in Recent JDK Releases](<https://devfeed.tech/articles/run-into-the-new-year-with-java-s-ahead-of-time-cache-features-23028.md>)

Original publisher: [Read original article](<https://www.javaadvent.com/2025/12/run-java-aot-cache-optimizations.html>)

Author: Ana-Maria Mihalceanu

Published: 2025-12-17T03:03:45Z

Content type: tutorial

Language: en

Sources: [Java Advent Calendar](<https://devfeed.tech/sources/java-advent-calendar.md>)

Topics: [Java](<https://devfeed.tech/topics/java.md>), [Caching](<https://devfeed.tech/topics/caching.md>), [JIT](<https://devfeed.tech/topics/jit.md>), [Memory safety verification](<https://devfeed.tech/topics/memory-safety-verification.md>)

Tags: [2025](<https://devfeed.tech/tags/2025.md>), [cache](<https://devfeed.tech/tags/cache.md>), [guides](<https://devfeed.tech/tags/guides.md>), [java](<https://devfeed.tech/tags/java.md>), [java-advent](<https://devfeed.tech/tags/java-advent.md>), [jdk](<https://devfeed.tech/tags/jdk.md>), [jdk25](<https://devfeed.tech/tags/jdk25.md>), [jit](<https://devfeed.tech/tags/jit.md>), [jvm](<https://devfeed.tech/tags/jvm.md>), [openjdk](<https://devfeed.tech/tags/openjdk.md>), [performance](<https://devfeed.tech/tags/performance.md>), [project-leyden](<https://devfeed.tech/tags/project-leyden.md>), [startup](<https://devfeed.tech/tags/startup.md>)

### AI overview

This tutorial explains how to use Ahead-of-Time cache features in recent JDK releases to improve Java application startup time and warm-up performance. It covers the train, assemble, and run workflow introduced in JDK 24 and method profiling improvements in JDK 25.

### Source excerpt

As the year comes to a close, turn your focus to boosting your Java application performance by applying Ahead-of-Time (AOT) cache features in recent JDK releases. This article guides you through using AOT cache optimizations in your application, thereby minimizing startup time and achieving faster peak performance. What is the Ahead-of-time cache in the jdk [...] The post Run Into the New Year with Java's Ahead-of-Time Cache Features appeared first on JVM Advent.

## Building a Java Agent to Generate a Karaoke Bar Schedule

DevFeed: [Building a Java Agent to Generate a Karaoke Bar Schedule](<https://devfeed.tech/articles/tinkering-with-a-hands-off-agent-23033.md>)

Original publisher: [Read original article](<https://www.javaadvent.com/2025/12/tinkering-with-a-hands-off-agent.html>)

Author: Tom Cools

Published: 2025-12-15T03:03:31Z

Content type: tutorial

Language: en

Sources: [Java Advent Calendar](<https://devfeed.tech/sources/java-advent-calendar.md>)

Topics: [Java](<https://devfeed.tech/topics/java.md>), [Optimization](<https://devfeed.tech/topics/optimization.md>), [Library](<https://devfeed.tech/topics/library.md>), [Framework](<https://devfeed.tech/topics/framework.md>), [Development](<https://devfeed.tech/topics/development.md>), [App](<https://devfeed.tech/topics/app.md>)

Tags: [2025](<https://devfeed.tech/tags/2025.md>), [agent](<https://devfeed.tech/tags/agent.md>), [building](<https://devfeed.tech/tags/building.md>), [development](<https://devfeed.tech/tags/development.md>), [java](<https://devfeed.tech/tags/java.md>), [java-advent](<https://devfeed.tech/tags/java-advent.md>), [library](<https://devfeed.tech/tags/library.md>), [optimization](<https://devfeed.tech/tags/optimization.md>)

### AI overview

This article describes experimenting with Langchain4J Agentic to build a Java agent that generates an optimization application from a problem description. The example scenario is a karaoke bar scheduler with rules for alternating singers and artists and with song start times.

### Source excerpt

It's great to write another entry for Java Advent this year! Last year, I wrote about how you can use Timefold Solver, an optimization library written in Java, to solve planning problems such as employee scheduling or, in true holiday spirit, optimizing Santa's travel route. This year, as the world is now all going "agentic", [...] The post Tinkering with a "hands-off" agent appeared first on JVM Advent.

## Java Hello World, LLVM Edition

DevFeed: [Java Hello World, LLVM Edition](<https://devfeed.tech/articles/java-hello-world-llvm-edition-23022.md>)

Original publisher: [Read original article](<https://www.javaadvent.com/2025/12/java-hello-world-llvm-edition.html>)

Author: James Hamilton

Published: 2025-12-07T02:02:37Z

Content type: tutorial

Language: en

Sources: [Java Advent Calendar](<https://devfeed.tech/sources/java-advent-calendar.md>)

Topics: [Java](<https://devfeed.tech/topics/java.md>), [LLVM](<https://devfeed.tech/topics/llvm.md>), [API](<https://devfeed.tech/topics/api.md>), [JIT](<https://devfeed.tech/topics/jit.md>)

Tags: [2025](<https://devfeed.tech/tags/2025.md>), [api](<https://devfeed.tech/tags/api.md>), [assembly](<https://devfeed.tech/tags/assembly.md>), [bytecode](<https://devfeed.tech/tags/bytecode.md>), [compilers](<https://devfeed.tech/tags/compilers.md>), [java](<https://devfeed.tech/tags/java.md>), [java-advent](<https://devfeed.tech/tags/java-advent.md>), [jdk](<https://devfeed.tech/tags/jdk.md>), [jit](<https://devfeed.tech/tags/jit.md>), [jvm](<https://devfeed.tech/tags/jvm.md>), [llvm](<https://devfeed.tech/tags/llvm.md>)

### AI overview

This tutorial shows how to use Java's Foreign Function & Memory API to call the LLVM C API, generate LLVM IR for a Hello World program, and JIT-compile it to native code. It also introduces LLVM, its IR representations, and local installation on Ubuntu or Debian.

### Source excerpt

After exploring Java bytecode in previous years (2022, 2023, 2024), this year we'll take an unexpected detour for a Java advent: instead of generating Java bytecode, we'll use Java to build and execute LLVM IR, the intermediate language behind compilers like clang. Using Java's Foreign Function & Memory (FFM) API, we'll call the LLVM C [...] The post Java Hello World, LLVM Edition appeared first on JVM Advent.

## How Understanding Request Flow in Spring Boot Changed the Way I Code

DevFeed: [How Understanding Request Flow in Spring Boot Changed the Way I Code](<https://devfeed.tech/articles/how-understanding-request-flow-in-spring-boot-changed-the-way-i-code-23021.md>)

Original publisher: [Read original article](<https://www.javaadvent.com/2025/12/how-understanding-request-flow-in-spring-boot-changed-the-way-i-code.html>)

Author: Mohammed

Published: 2025-12-03T02:02:20Z

Content type: article

Language: en

Sources: [Java Advent Calendar](<https://devfeed.tech/sources/java-advent-calendar.md>)

Topics: [Spring Boot](<https://devfeed.tech/topics/spring-boot.md>), [backend-development](<https://devfeed.tech/topics/backend-development.md>), [Framework](<https://devfeed.tech/topics/framework.md>), [Programming](<https://devfeed.tech/topics/programming.md>), [API](<https://devfeed.tech/topics/api.md>), [Database](<https://devfeed.tech/topics/database.md>)

Tags: [2025](<https://devfeed.tech/tags/2025.md>), [api](<https://devfeed.tech/tags/api.md>), [architecture](<https://devfeed.tech/tags/architecture.md>), [backend](<https://devfeed.tech/tags/backend.md>), [backend-development](<https://devfeed.tech/tags/backend-development.md>), [controllers](<https://devfeed.tech/tags/controllers.md>), [di](<https://devfeed.tech/tags/di.md>), [java](<https://devfeed.tech/tags/java.md>), [java-advent](<https://devfeed.tech/tags/java-advent.md>), [jpa](<https://devfeed.tech/tags/jpa.md>), [programming](<https://devfeed.tech/tags/programming.md>), [spring-boot](<https://devfeed.tech/tags/spring-boot.md>), [springboot](<https://devfeed.tech/tags/springboot.md>)

### AI overview

This article explains how tracing a request through a Spring Boot application helped the author understand layered backend architecture. It follows the flow from Controller to Service to Repository and Database, and discusses dependency injection, inversion of control, annotations, and the roles of application layers.

### Source excerpt

When I first stepped into backend development, I believed programming was only about one thing: "If the output comes, the job is done." I bundled everything into one giant file -- controllers, logic, database access.I didn't understand why Spring insisted on layers or why DI, IoC, and annotations were so important. The project structure looked [...] The post How Understanding Request Flow in Spring Boot Changed the Way I Code appeared first on JVM Advent.