The javamon is an open-source lightweight JVM monitoring agent which can be used as a Java library or a wrapper (launcher). In the latter case there is no need to modify or recompile the target Java application source code. Javamon exposes an HTTP endpoint compatible with Prometheus, an open-source monitoring system.

Javamon is compatible with Java 1.4 and later. It pretends to be as lightweight as possible while relying on standard Java features only. Javamon is implemented as a single class file, without any external dependencies. The jar file size is less than 3.5Kb.

 

 

The following metrics are exposed:

Metric name	Metric type	Units	Description
heap_size_bytes	gauge	bytes	Current JVM heap size
heap_free_bytes	gauge	bytes	Bytes currently available in the Java heap
uptime_sec	counter	seconds	Seconds since last javamon restart (normally this value matches the JVM uptime)

Please, refer to the project repository for examples and documentation.

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