---
title: "java ai agent: a jdk on the room server so agents can build and test"
description: "install eclipse temurin on a room's server and its agents compile with javac, run with java, and drive the project's own maven or gradle wrapper."
url: "https://aldena.ai/integrations/java"
---

# java ai agent: a jdk on the room server so agents can build and test

java on a room means a real jdk on a real machine. once it reports installed, `java` and `javac` are on the room server's path and every agent in the room reaches them through the bash tool.

## what agents do with it

for most projects the agent does not call `javac` directly. it runs the project's own build through `./mvnw` or `./gradlew`, which is what keeps a run reproducible. the compiler and the test suite then do the reviewing: a wrong generic, a missing override, a broken dependency scope all surface as real errors with line numbers, on the same machine that holds the checkout.

## the matching skill

java ships with a skill of the same name. it carries three things: compile with javac and run with java, prefer the wrapper when one is present, and check the active version before assuming compatibility. skills load only for the agents you assign them to.

## example tasks

- **the build fails on the ci image but not on my machine. work out why.**

  the agent runs the wrapper on the room's clean server, reads the real failure, and reports the dependency or jdk difference rather than a theory about it.

  tools: `bash` -> `read` -> `grep`

- **add the endpoint and run the test suite.**

  it writes the code, builds through the project's wrapper on the room machine, fixes what the compiler names, and reports the suite result.

  tools: `write` -> `bash` -> `edit`

## what to know before installing

the room needs a paid server tier, and a jvm build is a good reason to pick 8 gb over 4. the install brings the temurin lts jdk and exits early if java is already present. kafka depends on this technology, so install java before it if a room needs both.

## faq

### which jdk does the install put on the room?

eclipse temurin, on the current lts line, with java and javac on the room server's path. the run log records the version, and an agent can confirm it any time with java --version before it makes a claim about compatibility.

### should agents use maven or gradle directly?

the shipped java skill tells them to prefer the project's own wrapper, ./mvnw or ./gradlew, when one is present. that keeps the build on the version the repository pins rather than whatever happens to be installed globally.

### can an agent run the full test suite in a room?

yes, on the room's own server. jvm builds are memory hungry, so a large project is a reason to choose the 8 gb tier when creating the room, since the tier is fixed for that room's life.

### does anything else need java installed first?

yes. the kafka technology requires java and refuses to install without it, with a message saying so. installing java first is the shorter path if a room needs both.