Spring Add support for package-private BeanRegistrar in Spring AOT generated code

Comment From: joshlong

demo. generate a new project with no changes to the build on the initializr. im using maven. also, add GraalVM.

add a sub-packge, app, under the root Boot package, com.example.demo:

package com.example.demo.app;

import org.springframework.beans.factory.BeanRegistrar;
import org.springframework.beans.factory.BeanRegistry;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.core.env.Environment;

@Configuration
@Import(MyBeanRegistrar.class)
class MyConfig {}

class MyBeanRegistrar implements BeanRegistrar {

    @Override
    public void register(BeanRegistry registry, Environment env) {
        registry.registerBean(MyRunner.class);
    }
}

class MyRunner implements ApplicationRunner {

    @Override
    public void run(ApplicationArguments args) throws Exception {
        IO.println("Hello World");
    }
}

u will get

Total time:  1.528 s
[INFO] Finished at: 2025-12-03T09:35:03-08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:4.0.0:process-aot (process-aot) on project demo: Unable to compile generated source                                                                                                                                              
[ERROR] com.example.demo.app.MyBeanRegistrar is not public in com.example.demo.app; cannot be accessed from outside package /Users/jlong/Downloads/demo/target/spring-aot/main/sources/com/example/demo/DemoApplication__ApplicationContextInitializer.java 3:28                                                  
[ERROR] com.example.demo.app.MyBeanRegistrar is not public in com.example.demo.app; cannot be accessed from outside package /Users/jlong/Downloads/demo/target/spring-aot/main/sources/com/example/demo/DemoApplication__ApplicationContextInitializer.java 40:5                                                  
[ERROR] com.example.demo.app.MyBeanRegistrar is not public in com.example.demo.app; cannot be accessed from outside package /Users/jlong/Downloads/demo/target/spring-aot/main/sources/com/example/demo/DemoApplication__ApplicationContextInitializer.java 40:43                                                 
[ERROR] com.example.demo.app.MyBeanRegistrar is not public in com.example.demo.app; cannot be accessed from outside package /Users/jlong/Downloads/demo/target/spring-aot/main/sources/com/example/demo/DemoApplication__ApplicationContextInitializer.java 41:117                                                
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
➜  demo