if you use IntelliJ IDEA, adding the spring-boot-devtools is not enough. This is because unlike Eclipse, you need to explicitly tell IntelliJ IDEA to “Make The Project” for it to build to the target classpath.
see on youtube
The easiest solution: run app debug mode and press Ctrl + f9 (short-cut for build)
or
- You need to enable the “Make project automatically” option. You can
find it in Settings – Build, Execution, Deployment – Compiler - To open the registry, Press Ctrl-Alt-Shift-/ and select “Registry” from the menu that appears, enable the “compiler.automake.allow.when.app.running”
check-box.
