Automatic application restart shortens the development feedback loop. With Spring Boot DevTools active, changes to Java code or properties files trigger a restart after a brief delay, so updated behavior becomes visible without manually stopping and launching the application. section 1.3.5
DevTools makes the restart faster and limits what must be reloaded:
- It monitors project files, including content under src/main/, for changes. section 1.3.5
- It loads project code and dependency libraries through separate JVM class loaders. section 1.3.5
- When project code changes, it reloads the project class loader and restarts the Spring application context while retaining the dependency loader and JVM. section 1.3.5
- Dependency changes are not included in these automatic restarts and require a different restart path. section 1.3.5
Editing a project file
Change a Java class or properties file, wait briefly, and continue testing the running application after DevTools restarts the Spring application context. The JVM and unchanged dependency libraries remain available. section 1.3.5
