BeanNameAware

The BeanNameAware interface, which can be implemented by a bean that wants to obtain its own name, has a simple method: setBeanName(String). Spring calls the setBeanName() method after it has finished configuring your bean but before any life-cycle callbacks are called.

public class Singer implements BeanNameAware {
    private String name;

    @Override
    public void setBeanName(String name) {
        this.name = name;
    }
}

ApplicationContextAware

ApplicationContextAware is a Spring-specific interface that forces an implementation of a setter for an ApplicationContext object. It is automatically detected by the Spring IoC container, and the ApplicationContext that the bean is created in is injected into it. This is done after the constructor of the bean is called, so obviously using ApplicationContext in the constructor will lead to a NullPointerException.

Using the ApplicationContextAware interface, it is possible for your beans to get a reference to the ApplicationContext instance that configured them. The main reason this interface was created is to allow a bean to access Spring’s ApplicationContext in your application, for example, to acquire other Spring beans programmatically, using getBean(). You should, however, avoid this practice and use dependency injection to provide your beans with their collaborators. If you use the lookup-based getBean() approach to obtain dependencies when you can use dependency injection, you are adding unnecessary complexity to your beans and coupling them to the Spring framework without any good reason.

public class ShutdownHookBean implements ApplicationContextAware {
    @Override
    public void setApplicationContext(ApplicationContext ctx) throws BeansException {
        if (ctx instanceof GenericApplicationContext) {
            ((GenericApplicationContext)ctx).registerShutdownHook();
        }
    }
}