概述
通过Spring管理的类,默认是单例模式,但是如果有的类需要使用独立的属性,则需要配置为多例模式的. 但是多例模式不仅仅只是加一个声明,使用@Autowired进行注入,可能并不会是你想要的结果.因为多例模式的类是需要单独调用的.
不搞清楚原理直接测试：
需要多例的类上加上注解@Scope(“prototype”)

@Component
@Scope("prototype")
public class ExampleService{

	public void test(){
		System.out.println("test,current bean is" + this);
	}
	
}

引用直接使用@Autowired

@Controller
public class ExampleService{

	@Autowired
	private ExampleService exampleService;
	
	@RequestMapping("test")
	public void test(){
		exampleService.test();
	}
	
}

结果: 每个request过来的时候,exampleService实例均为同一个实例.

解决办法：
第一种：不使用@Autowired

@Controller
public class ExampleService{

	@Autowired
	private org.springframework.beans.factory.BeanFactory beanFactory;
	
	@RequestMapping("test")
	public void test(){
		ExampleService exampleService = beanFactory.getBean(ExampleService.class);
		exampleService.test();
	}
}

第二种：使用bean工厂

@Autowired
 private ApplicationContext context;


 @Bean
    public WebSocketHandler websocketBHandler() {
        PerConnectionWebSocketHandler perConnectionHandler = new PerConnectionWebSocketHandler(WebSocketBHandler.class);
        perConnectionHandler.setBeanFactory(context.getAutowireCapableBeanFactory());
        //设置bean工厂，否则bean工厂WebSocketBHandler将不会自动连接
        return perConnectionHandler;
    }

然后使用ApplicationContext进行代理bean工厂

注入
@Autowired
private ApplicationContext context;
使用
this.Bservice = context.getBean(BService.class, this);

官方文档说明
4.5.3 Singleton beans with prototype-bean dependencies When you use singleton-scoped beans with dependencies on prototype beans, be aware that dependencies are resolved at instantiation time. Thus if you dependency-inject a prototype-scoped bean into a singleton-scoped bean, a new prototype bean is instantiated and then dependency-injected into the singleton bean. The prototype instance is the sole instance that is ever supplied to the singleton-scoped bean. However, suppose you want the singleton-scoped bean to acquire a new instance of the prototype-scoped bean repeatedly at runtime. You cannot dependency-inject a prototype-scoped bean into your singleton bean, because that injection occurs only once, when the Spring container is instantiating the singleton bean and resolving and injecting its dependencies. If you need a new instance of a prototype bean at runtime more than once, see Section 4.4.6, “Method injection”
《参考：https://eoekun.top/2017/07/Spring多例使用@Autowired无效》