Spring如何利用三级缓存解密解决循环依赖难题

@Component
public class ServiceA {
    @Autowired
    private ServiceB serviceB; // 需要ServiceB实例
}

@Component
public class ServiceB {
    @Autowired
    private ServiceA serviceA; // 需要ServiceA实例
}

// 实例化后立即注册
addSingletonFactory(beanName, () -> getEarlyBeanReference(beanName, bean));

protected Object getEarlyBeanReference(String beanName, Object bean) {
    for (BeanPostProcessor bp : getBeanPostProcessors()) {
        if (bp instanceof SmartInstantiationAwareBeanPostProcessor) {
            // 动态决策是否创建代理
            bean = ((SmartInstantiationAwareBeanPostProcessor) bp)
                       .getEarlyBeanReference(bean, beanName);
        }
    }
    return bean;
}

public Object getEarlyBeanReference() {
    // 延迟点1：只在被依赖时触发
    // 延迟点2：动态决定是否创建代理
    return (needsProxy ? createProxy(bean) : bean); 
}

// 最终代理一致性保证
public void initializeBean() {
    if (earlyProxyReference != null) {
        return earlyProxyReference; // 复用已创建的代理
    }
    return createProxy(bean); // 无循环依赖时创建
}

@Service
public class UserService {
    @Autowired 
    private OrderService orderService;
    
    @Transactional // 需要代理
    public void createUser() {...}
}

// 使用事件解耦
applicationContext.publishEvent(new UserCreatedEvent(user));

@Lazy
@Autowired
private HeavyService heavyService; // 延迟初始化

@Scope(value = WebApplicationContext.SCOPE_REQUEST, proxyMode = ScopedProxyMode.TARGET_CLASS)
public class RequestScopedBean {...}