Installation

Requirements

  • JDK 17 or newer to run (the one Java-17-bytecode build is verified on 17 / 21 / 25). jvmlens reads JFR via jdk.jfr.consumer.

Get the tools

jvmlens ships as a small set of jars — pick what you need:

Jar What it’s for

jvmlens.jar

the CLI (analyze / profile / bench / watch / trend / control / mcp)

jvmlens-agent.jar

the in-process -javaagent (periodic summaries, dimensions, history)

jvmlens-jmh.jar

the JMH profiler plugin (engine + profiler, no Spring/picocli)

org.alexmond:jvmlens-engine

the dependency-free library (embed the summarizer)

Option 1 — download a release jar (CLI / agent / JMH)

The CLI, agent, and JMH jars are GitHub release assets (they’re runnable artifacts, not library dependencies). Grab them from the releases page, or with the gh CLI:

gh release download 0.3.0 -R alexmond/jvmlens -p 'jvmlens.jar'
# pre-release rolling build (latest main): use `latest` instead of the tag
gh release download latest -R alexmond/jvmlens -p 'jvmlens.jar' -p 'jvmlens-agent.jar' -p 'jvmlens-jmh.jar'

Option 2 — depend on the engine (Maven Central)

To embed the summarizer in your own tool, depend on jvmlens-engine (dependency-free, only jdk.jfr.consumer). The JMH profiler is published too, so a benchmark module can depend on it:

<dependency>
  <groupId>org.alexmond</groupId>
  <artifactId>jvmlens-engine</artifactId>
  <version>0.3.0</version>
</dependency>

API docs: jvmlens-engine Javadoc (hosted on javadoc.io once the version is published).

Option 3 — build from source

git clone [email protected]:alexmond/jvmlens.git
cd jvmlens
./mvnw clean package

This is a Maven reactor; the jars land in per-module target/ dirs:

  • jvmlens-cli/target/jvmlens.jar

  • jvmlens-agent/target/jvmlens-agent.jar

  • jvmlens-jmh/target/jvmlens-jmh.jar

Option 4 — install the Claude Code skills

To drive jvmlens from a coding agent, this repo is also a Claude Code plugin marketplace:

/plugin marketplace add alexmond/jvmlens
/plugin install jvmlens-perf@jvmlens       # dev-time optimize→measure loop
/plugin install jvmlens-monitor@jvmlens    # long-running monitor + trend

Each skill fetches the jvmlens jar itself (Options 1–3 above), so this is enough on its own. See jvmlens + your AI agent for sample usage.

Run

java -jar jvmlens.jar analyze recording.jfr

See Usage for the full command reference.