Automatic registrar of even sourcing repository bean

EventSourcingRepositoryBeanDefinitionRegistrar.java

package mysystem;

import org.axonframework.commandhandling.model.Repository;
import org.axonframework.eventsourcing.EventSourcingRepository;
import org.axonframework.spring.stereotype.Aggregate;
import org.jetbrains.annotations.NotNull;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
import org.springframework.core.ResolvableType;
import org.springframework.core.type.AnnotationMetadata;

public class EventSourcingRepositoryBeanDefinitionRegistrar implements
    ImportBeanDefinitionRegistrar, BeanFactoryAware {

    private DefaultListableBeanFactory beanFactory;

    @Override
    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
        this.beanFactory = (DefaultListableBeanFactory) beanFactory;
    }

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
        String[] aggregatesBeanNames = beanFactory.getBeanNamesForAnnotation(Aggregate.class);
        for (String aggregateBeanName : aggregatesBeanNames) {
            BeanDefinition aggregateBeanDef = beanFactory.getBeanDefinition(aggregateBeanName);
            try {
                registerRepositoryBean(aggregateBeanName, aggregateBeanDef.getBeanClassName());
            } catch (ClassNotFoundException e) {
                throw new RuntimeException(e);
            }
        }
    }

    private void registerRepositoryBean(String aggregateBeanName, String aggregateClassName) throws ClassNotFoundException {
        Class<?> aClass = Class.forName(aggregateClassName);
        EventSourced annotation = beanFactory.findAnnotationOnBean(aggregateBeanName, EventSourced.class);
        if (annotation != null) {
            RootBeanDefinition repBeanDef = (RootBeanDefinition) BeanDefinitionBuilder.rootBeanDefinition(EventSourcingRepository.class)
                .addConstructorArgValue(aClass)
                .addConstructorArgReference("eventBus")
                .getRawBeanDefinition();
            repBeanDef.setTargetType(
                ResolvableType.forClassWithGenerics(Repository.class, aClass));

            String repositoryName = getRepositoryName(aggregateBeanName);
            beanFactory.registerBeanDefinition(repositoryName, repBeanDef);
        }
    }

    @NotNull
    private String getRepositoryName(String aggregateBeanName) {
        return aggregateBeanName.substring(0, 1).toLowerCase() 
            + aggregateBeanName.substring(1) + "Repository";
    }
}