This version is still in development and is not considered stable yet. For the latest stable version, please use Micrometer 1.13.0!

Apache Tomcat Metrics Instrumentation

The Apache Tomcat software is an open source implementation of the Jakarta Servlet, Jakarta Server Pages, Jakarta Expression Language, Jakarta WebSocket, Jakarta Annotations and Jakarta Authentication specifications.

// Setting up instrumentation
SimpleMeterRegistry registry = new SimpleMeterRegistry(SimpleConfig.DEFAULT, new MockClock());


Iterable<Tag> tags = Tags.of("metricTag", "val1");
TomcatMetrics.monitor(registry, manager, tags);

// Example of Tomcat metrics
assertThat(registry.get("tomcat.sessions.active.max").tags(tags).gauge().value()).isEqualTo(3.0);
assertThat(registry.get("tomcat.sessions.active.current").tags(tags).gauge().value()).isEqualTo(2.0);
assertThat(registry.get("tomcat.sessions.expired").tags(tags).functionCounter().count()).isEqualTo(1.0);
assertThat(registry.get("tomcat.sessions.rejected").tags(tags).functionCounter().count()).isEqualTo(1.0);
assertThat(registry.get("tomcat.sessions.created").tags(tags).functionCounter().count()).isEqualTo(3.0);
assertThat(registry.get("tomcat.sessions.alive.max").tags(tags).timeGauge().value()).isGreaterThan(1.0);