@ActiveProfiles is a class-level annotation that is used to instruct the Spring TestContext Framework to record all application events that are published in the ApplicationContext during the execution of a single test.

@ActiveProfiles is a class-level annotation that you can use to configure how the Spring TestContext Framework is bootstrapped.

@ActiveProfiles is a class-level annotation that you can use to configure the locations of properties files and inlined properties to be added to the set of PropertySources in the Environment for an ApplicationContext loaded for an integration test.

@ActiveProfiles is a class-level annotation that is used to declare which bean definition profiles should be active when loaded an ApplicationContext for an integration test.

Call LegacySingleton.getInstance() from within a @Bean method and return the instance.

Return an instance of LegacySingleton using the new keyword from a @Bean method.

It is not possible without modifying the LegacySingleton class, the constructor must be public.

Modify the LegacySingleton class by adding the @Autowired annotation to the instance variable.

An external monitoring system must be used with Actuator.

The metrics endpoint /actuator/metrics is exposed over HTTP by default.

Timer measures both the number of timed events and the total time of all events timed.

Custom metrics can be measured using Meter primitives such as Counter, Gauge, Timer, and DistributionSummary.

A metric must be created with one or more tags.