boot_metrics.java

@Controller
@Description("A controller for handling requests for hello messages")
public class SampleController {

	@Autowired
	private HelloWorldService helloWorldService;

	@Autowired
	private GaugeService gauges;

	@GetMapping("/")
	@ResponseBody
	public Map<String, String> hello() {
		this.gauges.submit("timer.test.value", Math.random() * 1000 + 1000);
		return Collections.singletonMap("message",
				this.helloWorldService.getHelloMessage());
	}

	protected static class Message {

		@NotBlank(message = "Message value cannot be empty")
		private String value;

		public String getValue() {
			return this.value;
		}

		public void setValue(String value) {
			this.value = value;
		}
	}

}

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
@DirtiesContext
public class SampleDropwizardMetricsApplicationTests {

	@Autowired
	private MetricRegistry registry;

	@Autowired
	private GaugeService gauges;

	@Test
	public void timerCreated() {
		this.gauges.submit("timer.test", 1234);
		assertThat(this.registry.getTimers().get("timer.test").getCount()).isEqualTo(1);
	}

}

<dependency>
			<groupId>io.dropwizard.metrics</groupId>
			<artifactId>metrics-core</artifactId>
</dependency>