Package org.springframework.boot.autoconfigure.condition

Annotation Type ConditionalOnBean

  • @Target({TYPE,METHOD})
@Retention(RUNTIME)
@Documented
@Conditional(org.springframework.boot.autoconfigure.condition.OnBeanCondition.class)
public @interface ConditionalOnBean
    Conditional that only matches when beans meeting all the specified requirements are already contained in the BeanFactory. All the requirements must be met for the condition to match, but they do not have to be met by the same bean.

    When placed on a @Bean method, the bean class defaults to the return type of the factory method: 

     @Configuration
 public class MyAutoConfiguration {

     @ConditionalOnBean
     @Bean
     public MyService myService() {
         ...
     }

 }

    In the sample above the condition will match if a bean of type MyService is already contained in the BeanFactory.

    The condition can only match the bean definitions that have been processed by the application context so far and, as such, it is strongly recommended to use this condition on auto-configuration classes only. If a candidate bean may be created by another auto-configuration, make sure that the one using this condition runs after.

    • Optional Element Summary

      Optional Elements 
      Modifier and TypeOptional ElementDescription
      Class<? extends Annotation>[]annotation
      The annotation type decorating a bean that should be checked.
      String[]name
      The names of beans to check.
      Class<?>[]parameterizedContainer
      Additional classes that may contain the specified bean types within their generic parameters.
      SearchStrategysearch
      Strategy to decide if the application context hierarchy (parent contexts) should be considered.
      String[]type
      The class type names of beans that should be checked.
      Class<?>[]value
      The class types of beans that should be checked.

    • Element Detail

      • value

        Class<?>[] value
        The class types of beans that should be checked. The condition matches when beans of all classes specified are contained in the BeanFactory.
        Returns:
        the class types of beans to check
        Default:
        {}

      • type

        String[] type
        The class type names of beans that should be checked. The condition matches when beans of all classes specified are contained in the BeanFactory.
        Returns:
        the class type names of beans to check
        Default:
        {}

      • annotation

        Class<? extends Annotation>[] annotation
        The annotation type decorating a bean that should be checked. The condition matches when all of the annotations specified are defined on beans in the BeanFactory.
        Returns:
        the class-level annotation types to check
        Default:
        {}

      • name

        String[] name
        The names of beans to check. The condition matches when all of the bean names specified are contained in the BeanFactory.
        Returns:
        the names of beans to check
        Default:
        {}

      • search

        SearchStrategy search
        Strategy to decide if the application context hierarchy (parent contexts) should be considered.
        Returns:
        the search strategy
        Default:
        org.springframework.boot.autoconfigure.condition.SearchStrategy.ALL

      • parameterizedContainer

        Class<?>[] parameterizedContainer
        Additional classes that may contain the specified bean types within their generic parameters. For example, an annotation declaring value=Name.class and parameterizedContainer=NameRegistration.class would detect both Name and NameRegistration<Name>.
        Returns:
        the container types
        Since:
        2.1.0
        Default:
        {}