JMX Metrics Quick Access with Java
HiveMQ, a robust and highly configurable MQTT broker, extends its functionality by offering an extensive array of metrics via Java Management Extensions (JMX): https://docs.hivemq.com/hivemq/latest/user-guide/monitoring.html#jmx. This empowers users to engage in efficient monitoring through widely recognized JMX monitoring tools like JConsole.
In addition to the plethora of visualization tools like Prometheus, Grafana, and Datadog available in the realm of monitoring, there is substantial merit in acquiring an overview of these metrics using pure Java tooling. This article serves as a comprehensive resource, offering practical Java examples for listing all accessible metrics and facilitating the extraction of metric values.
Instructions
List all available metrics
Compilation
javac JMXListAllMetrics.java
Execution
java JMXListAllMetrics
Scrape one metric periodically
Compilation
Execution
Replace
<ObjectName>
with the desired metric's ObjectName and<DelayInMillis>
with the desired delay between checks in milliseconds.
Dependencies for JMX are already included in the JDK, making it easy to access and monitor HiveMQ metrics with these Java programs.
Note: Ensure that you have the necessary permissions and network access to connect to the remote JMX server and access the HiveMQ metrics:
https://docs.hivemq.com/hivemq/latest/user-guide/monitoring.html#_configuration