ConditionalOnProperty

@ConditionalOnProperty is a Spring Boot annotation that is used to conditionally enable a bean or a configuration class based on the presence or value of a specific property in the application's configuration files.

The annotation can be applied to a class or a method, and it takes one or more property names as arguments. By default, the annotation checks if the property exists and has a non-empty value. However, you can also specify additional conditions using the "havingValue" and "matchIfMissing" attributes.

Example usage:

@Configuration
@ConditionalOnProperty(name = "myapp.feature.enabled", havingValue = "true")
public class MyFeatureConfiguration {
   // Configuration code here
}

In the above example, the "MyFeatureConfiguration" class will only be enabled if the property "myapp.feature.enabled" is set to "true" in the configuration files.

You can also use the "matchIfMissing" attribute to define the behavior when the property is not present. By default, if the property is missing, the bean or configuration class will not be enabled. However, if you set "matchIfMissing" to "true", the bean or configuration class will be enabled even if the property is missing.

@Configuration
@ConditionalOnProperty(name = "myapp.feature.enabled", matchIfMissing = true)
public class MyFeatureConfiguration {
   // Configuration code here
}

In this example, the "MyFeatureConfiguration" class will be enabled if the property "myapp.feature.enabled" is set to any value, or if the property is not present at all in the configuration files.

Overall, @ConditionalOnProperty is a powerful annotation in Spring Boot that allows you to conditionally enable beans or configuration classes based on the presence or value of specific properties in the application's configuration files