java spring-boot actuator monitoring metrics

Actuator for production monitoring

David Kumar Jan 2026

4 tabs

package com.example.demo.service;

import io.micrometer.core.instrument.Counter;
import io.micrometer.core.instrument.MeterRegistry;
import io.micrometer.core.instrument.Timer;
import org.springframework.stereotype.Service;

@Service
public class MetricsService {

    private final Counter userCreationCounter;
    private final Timer userProcessingTimer;
    private final MeterRegistry registry;

    public MetricsService(Counter userCreationCounter,
                         Timer userProcessingTimer,
                         MeterRegistry registry) {
        this.userCreationCounter = userCreationCounter;
        this.userProcessingTimer = userProcessingTimer;
        this.registry = registry;
    }

    public void recordUserCreation() {
        userCreationCounter.increment();
    }

    public void recordProcessingTime(Runnable task) {
        userProcessingTimer.record(task);
    }

    public void recordActiveUsers(int count) {
        registry.gauge("users.active", count);
    }
}

management:
  endpoints:
    web:
      exposure:
        include: health,info,metrics,prometheus,env,loggers
      base-path: /actuator
  endpoint:
    health:
      show-details: when-authorized
      probes:
        enabled: true
    shutdown:
      enabled: true
  server:
    port: 9090
  metrics:
    export:
      prometheus:
        enabled: true
    tags:
      application: user-service
      environment: production

info:
  app:
    name: '@project.name@'
    version: '@project.version@'
    description: User Management Service
    encoding: '@project.build.sourceEncoding@'
    java:
      version: '@java.version@'

package com.example.demo.actuator;

import org.springframework.boot.actuate.health.Health;
import org.springframework.boot.actuate.health.HealthIndicator;
import org.springframework.stereotype.Component;

@Component
public class CustomHealthIndicator implements HealthIndicator {

    @Override
    public Health health() {
        try {
            // Check external service availability
            boolean externalServiceUp = checkExternalService();

            if (externalServiceUp) {
                return Health.up()
                    .withDetail("externalService", "Available")
                    .withDetail("responseTime", "45ms")
                    .build();
            } else {
                return Health.down()
                    .withDetail("externalService", "Unavailable")
                    .build();
            }
        } catch (Exception e) {
            return Health.down()
                .withDetail("error", e.getMessage())
                .build();
        }
    }

    private boolean checkExternalService() {
        // Implementation to check external service
        return true;
    }
}

package com.example.demo.config;

import io.micrometer.core.instrument.Counter;
import io.micrometer.core.instrument.MeterRegistry;
import io.micrometer.core.instrument.Timer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MetricsConfig {

    @Bean
    public Counter userCreationCounter(MeterRegistry registry) {
        return Counter.builder("users.created")
            .description("Number of users created")
            .tag("type", "registration")
            .register(registry);
    }

    @Bean
    public Timer userProcessingTimer(MeterRegistry registry) {
        return Timer.builder("users.processing.time")
            .description("Time taken to process user requests")
            .register(registry);
    }
}

4 files · java, yaml Explain with highlit

Spring Boot Actuator provides production-ready features—health checks, metrics, info endpoints. /actuator/health shows application status for load balancers. /actuator/metrics exposes JVM metrics, HTTP stats, custom metrics. /actuator/info displays application metadata. Custom health indicators check dependencies—database, Redis, external APIs. Micrometer integrates with monitoring systems like Prometheus, Grafana, Datadog. Endpoint security restricts sensitive data. Management port separates actuator from application traffic. Graceful shutdown enables zero-downtime deployments. Custom endpoints extend functionality. Actuator enables observability—essential for debugging production issues, capacity planning, and SLA monitoring. I expose relevant endpoints based on environment and secure them appropriately.