Log spring Bean instantiation

Question

How can we log each bean instantiation in Spring?

• I wish to log a message every time a bean is initialized.
• I have N number of bean and I don't want to put any logger on init method for each bean.
• I see this as a cross-cutting concern, but not sure how to achieve this.

Is there a way.?

Answer 1

You can use a BeanPostProcessor

@Component
public class LogBeanPostProcessor implements BeanPostProcessor {

    @Override
    public Object postProcessBeforeInitialization(Object bean, String beanName)
        throws BeansException {
        return bean;
    }

    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName)
        throws BeansException {
        LOGGER.log(String.format("Bean instantiated with name %s and class %s", beanName, bean.getClass().getSimpleName()));
        return bean;
    }
}