如何通过varargs（程序参数）条件排除Spring bean？

Question

How can I let spring evaluate varargs and run beans conditionally?

@SpringBootConfiguration
public class Application {
  public static void main(String[] args) {
    SpringApplication.run(Application.class);
  }
}

@Service
@Order(1) //run if no vararg is given
public class Job1 implements ApplicationRunner {
}

@Service
@Order(2) //TODO run only if a "job2" occurs as vararg
public class Job2 implements ApplicationRunner {
}

Question: I want to start those jobs conditionally by varargs given from command line on application start. Is that possible?

Answer 1

How about you use @ConditionalOnProperty on those beans and you pass the property to include/exclude them from the command line?

A full example could be:

@Service
@Order(1) //run if no vararg is given
@ConditionalOnProperty(name = "my.property", havingValue = "job1")
public class Job1 implements ApplicationRunner {
}

@Service
@Order(2) //TODO run only if a "job2" occurs as vararg
@ConditionalOnProperty(name = "my.property", havingValue = "job2")
public class Job2 implements ApplicationRunner {
}

and then you pass the property with:

mvn spring-boot:run -Dspring-boot.run.arguments="--my.property=job1/job2"

Another option could be removing @Component/@Service from the Job1/Job2 classes and in a configuration class creating a bean like:

@Bean
public ApplicationRunner applicatinRunner(ApplicationArguments arguments) throws IOException {
        String commandLineArgument = arguments.getSourceArgs()[0];
        //your logic here to decide which one you want to instantiate
        return new Job1()/Job2();
}

Answer 2

It's possible by simply implementing a custom Condition and evaluating ApplicationArguments . The arguments I was looking for are called non-optional args by Spring:

class Job2Condition implements Condition {
    @Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
        return context.getBeanFactory()
                .getBean(ApplicationArguments.class)
                .getNonOptionArgs()
                .contains("job2");
    }
}

@Component
@Conditional(Job2Condition.class)
public class Job2 implements ApplicationRunner {
}