Create a custom JMX MBean in AEM to expose application metrics

Hi @matthewda19,

You can register custom JMX MBeans via OSGi services, enabling you to expose application-specific metrics (eg. API call counts, cache hit/miss ratios) through the /system/console/jmx console.

1. Define an MBean Interface
   The interface should follow the SomethingMBean naming convention:

   public interface CustomMetricsMBean { int getApiCallCount(); void resetApiCallCount(); }

2. Implement the MBean
   Implement the interface in a class and annotate it as an OSGi component:

   import org.osgi.service.component.annotations.Component; import org.apache.felix.scr.annotations.Service; @Component(service = CustomMetricsMBean.class, immediate = true) public class CustomMetrics implements CustomMetricsMBean { private int apiCallCount = 0; @Override public int getApiCallCount() { return apiCallCount; } @Override public void resetApiCallCount() { apiCallCount = 0; } // Increment this from your service logic public void incrementApiCallCount() { apiCallCount++; } }

3. Access the JMX Console
   Once deployed, navigate to:
   http://localhost:4502/system/console/jmx
   Search for your MBean by its name (eg. org.example: type=CustomMetrics).

4. Best Practices

   • Use clear naming like com.companyname:type=ProjectName,service=CustomMetrics.

   • Keep your MBean lightweight - avoid expensive operations in getters.