Spring order to load a configuration class using spring-boot @ConditionalOnMissingBean?

Question

I would like to enable custom setup and reasonable defaults with @ConditionalOnMissingBean? I have a spring boot application:

@Configuration
@Import({CustomConfiguration.class, DefaultConfiguration.class})
@EnableAutoConfiguration(exclude={MetricFilterAutoConfiguration.class})
public class Application {

    @Autowired
    ErrorListener errorListener;
}

and a CustomConfiguration, which allow either spring xml or component scanning:

@Configuration("customConfiguration")
@ImportResource("classpath:customContext.xml")
@ComponentScan({"org.custom.impl"})
public class CustomConfiguration

DefaultConfigurationuses ConditionalOnMissingBean:

@Bean
@ConditionalOnMissingBean 
ErrorListener errorListener() {
     return new LoggingErrorListener();
}

What I'm trying to achieve allows you to specify custom ErrorListeneron the classpath, if not defined then use the default value LoggingErrorListener(via ConditionalOnMissingBean). I found that it is DefaultConfigurationalways used before CustomConfiguration.

I experimented with @DependsOnand @Order, but without joy.

Answer 1

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Answer 2

: , beans, Spring Boot. , Spring RestTemplate, . @ConditionalOnMissingBean, , :

@Bean
@ConditionalOnMissingBean(RestTemplate.class)
public RestTemplate restTemplate() {

    return new RestTemplate();
}

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, , @ConditionalOnMissingBean @Configuration @Beans . , . , @Component.