Closed
Description
I would like Spring Boot autoconfiguration to be a public (or at least package-private) contract, so that I can use it to create functional bean registrations with all the same features. There's a barrier to doing that, which is that there are some private types that can't be used, even from a class in the same package.
There are a bunch of these in Spring Boot autoconfiguration, generally following one of two patterns. The first is a private class with a public interface, e.g. in ErrorMvcAutoConfiguration:
@Bean
public ErrorPageCustomizer errorPageCustomizer() {
return new ErrorPageCustomizer(this.serverProperties);
}
private static class ErrorPageCustomizer implements ErrorPageRegistrar, Ordered {
...
}The second is a private class with a private interface, e.g. in WebMvcAutoConfiguration:
@Configuration
@ConditionalOnEnabledResourceChain
static class ResourceChainCustomizerConfiguration {
@Bean
public ResourceChainResourceHandlerRegistrationCustomizer resourceHandlerRegistrationCustomizer() {
return new ResourceChainResourceHandlerRegistrationCustomizer();
}
}
interface ResourceHandlerRegistrationCustomizer {
void customize(ResourceHandlerRegistration registration);
}
private static class ResourceChainResourceHandlerRegistrationCustomizer
implements ResourceHandlerRegistrationCustomizer {
...
}