https://github.com/javamelody/javamelody/wiki

JavaMelody : monitoring of JavaEE applications
https://github.com/javamelody/javamelody
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Recent commits:

• Chinese traditional (Taïwan), evernat
• fix version_alert, evernat
• aggregation in collect server: hits are increasing each minute with all the hits of monitored applications if the collect server is not restarted after adding the aggregationhttps://stackoverflow.com/questions/65397953/javamelody-collector-server-counting-error-number-of-hits-increase-exponentiall/65429394?noredirect=1#comment115695003_65429394, evernat
• fix hits are counted twice in aggregations and aggregated of collect server, evernat
• add @ConditionalOnMissingBean on SchedulerFactoryBeanCustomizer (#973), GitHub

Enabling Tomcat Performance Monitoring with JavaMelody

If you’re using Maven, simply add the javamelody-core dependency to the pom.xml:

<dependency>
    <groupId>net.bull.javamelody</groupId>
    <artifactId>javamelody-core</artifactId>
    <version>1.69.0</version>
</dependency>

In this way, you can enable monitoring for your web application.

After deploying the application on Tomcat, you can access the monitoring screens at the /monitoring URL.

JavaMelody contains useful graphs for displaying information related to various performance measures, as well as a way to find the values of the Tomcat JMX beans.

Most of these beans are JVM-specific and not application-specific.

Let’s go through each of the most important metrics – and see what MBeans are available and other ways to monitor them.