Performing AOT processing of a logback configuration xml with variables as the class name throws a java.lang.ClassNotFoundException in org.springframework.boot.logging.logback.SpringBootJoranConfigurator.

I have created a reproducer at https://github.com/justin-tay/spring-boot-logback-issue which demonstrates the issue.

Running mvnw spring-boot:run shows that it runs normally and logback substitutes the variable for the class name.

Running mvnw spring-boot:process-aot shows the exception.

In logback the relevant code performing the substitution is

https://github.com/qos-ch/logback/blob/bba7a908c87a4a483860f6d49695ec2348c56e49/logback-core/src/main/java/ch/qos/logback/core/model/processor/ImplicitModelHandler.java#L126

I think that in Spring Boot the following should also likewise add code to perform the substitution

https://github.com/spring-projects/spring-boot/blob/7d697310a093bfd46ce28fcb50f0653004044012/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java#L260