Spring Boot中的属性顺序

Question

I want to write my own Spring Boot starter and let it inherit from another starter (let's say spring-boot-starter-batch). Now I want to set one of spring-boot-starter-batch properties to a default that differs from spring-boot-starter-batch's default (for example spring.batch.job.enabled=false instead of true). The user of my starter shall still be able to override it via application.properties .

That's not really possible, right? The order for reading properties is the following:

1. Command line arguments.
2. Java System properties ( System.getProperties() ).
3. OS environment variables.
4. JNDI attributes from java:comp/env
5. A RandomValuePropertySource that only has properties in random.* .
6. @PropertySource annotations on your @Configuration classes.
7. Application properties outside of your packaged jar ( application.properties including YAML and profile variants).
8. Application properties packaged inside your jar ( application.properties including YAML and profile variants).
9. Default properties (specified using SpringApplication.setDefaultProperties ).

So if I use @PropertySource in my starter to set the property, the user of my starter won't be able to override it via application.properties . Wouldn't it make sense to change the order and set @PropertySource at number 8?

Or is there a way to achieve what I want?

Answer 1

The order of @PropertySource is definitely up for debate. Before that debate though you should be able to add your own property sources in a listener or initializer (like the existing config file listener).