使用Spring @DependsOn控制bean加载顺序的实例

import java.util.ArrayList;
import java.util.List;
import java.util.function.Consumer;
public class EventManager {
    private final List<Consumer<String>> listeners = new ArrayList<>();
    private EventManager() {
    }
    private static class SingletonHolder {
        private static final EventManager INSTANCE = new EventManager();
    }
    public static EventManager getInstance() {
        return SingletonHolder.INSTANCE;
    }
    public void publish(final String message) {
        listeners.forEach(l -> l.accept(message));
    }
    public void addListener(Consumer<String> eventConsumer) {
        listeners.add(eventConsumer);
    }
}

import com.logicbig.example.EventManager;
public class EventPublisherBean {
    public void initialize() {
        System.out.println("EventPublisherBean initializing");
        EventManager.getInstance().publish("event published from EventPublisherBean");
    }
}

import com.logicbig.example.EventManager;
public class EventListenerBean {
    private void initialize() {
        EventManager.getInstance().
                addListener(s ->
                        System.out.println("event received in EventListenerBean : " + s));
    }
}

@Configuration
@ComponentScan("com.logicbig.example")
public class AppConfig {
    @Bean(initMethod = "initialize")
    @DependsOn("eventListener")
    public EventPublisherBean eventPublisherBean () {
        return new EventPublisherBean();
    }
    @Bean(name = "eventListener", initMethod = "initialize")
    // @Lazy
    public EventListenerBean eventListenerBean () {
        return new EventListenerBean();
    }
    public static void main (String... strings) {
        new AnnotationConfigApplicationContext(AppConfig.class);
    }
}

EventPublisherBean initializing