Spring Boot @ConditionalOnExpression Annotation Example
In this section we will learn about @ConditionalOnExpression Annotation. The @ConditionalOnExpression annotation allows configurations based on the result of a SpEL expression. The @ConditionalOnExpression annotation may be used on any class annotated with @Configuration , @Component , @Service & @Repository or on methods annotated with @Bean . 1. Using @ConditionalOnExpression on @Bean method To illustrate the use of @ConditionalOnExpression , we will develop a basic notification system. To keep things simple for now, let's assume we want to send email notifications and sms notifications. Define our application custom configuration properties, notification.enabled = true notification.sms.enabled = true notification.email.enabled = false notification.twitter.enabled = true Next, we'll need to create a simple service to send a notification. For example, consider the Notification Sender interface: public interface NotificationService { } In this example, the S