Spring provides the ApplicationStartup interface to track and analyze application context creation during startup. Three implementations are covered: DefaultApplicationStartup (no-op), BufferingApplicationStartup (stores events in memory, accessible via actuator endpoint or programmatically), and FlightRecorderApplicationStartup (integrates with Java Flight Recorder/JMC). The tutorial shows how to configure each, access recorded startup steps, add custom steps using @PostConstruct, write tests with SpringBootTest.UseMainMethod.ALWAYS, and implement a fully custom ApplicationStartup for real-time monitoring during context creation.
Table of contents
1. Introduction2. Spring Application Context3. The ApplicationStartup Interface4. BufferingApplicationStartup5. FlightRecorderApplicationStartup6. Adding Custom Steps7. Implementing the ApplicationStartup Interface8. Conclusion3K Impressions