如何访问位于@Service Class中的SseEmitters集合

Question

sses映射已从MessageController类移动到用@ServiceMessageTemplate.class注释的类。现在，我们需要一种方法来将SseEmitter实例(在openConn()中创建(添加到MessageTemplate类中的sses映射中。

Map在这里可能不是最好的选择，如果是的话，还有什么其他缓存替代方案可用，因为我需要一个away来将消息发送回各个客户端？

@Controller
@RequestMapping(value="/")
public class MessageController{
@Autowired MessageOperations mesgOps;
//Moved to MessageTemplate
Map<String, SseEmitter> sses = new ConcurrentHashMap<>();
@GetMapping(value = "/conn/{username}")
public SseEmitter openConn(@PathVariable("username") String username){
SseEmitter sseEmitter = new SseEmitter(3600000L);
sses.put(username, sseEmitter);
return sseEmitter;
}

@Service 
public class MessageTemplate implements MessageOperations{
//The above map now resides here.
Map<String, SseEmitter> sses = new ConcurrentHashMap<>();
..
}

Answer 1

假设问题中所有呈现的抽象都是"自定义"的(在您的组织中编写的代码(，并且它们本身不属于spring生态系统，我看到以下内容：

1. MessageTemplate是由spring驱动的单例作用域bean
2. 控制器也是一个单例bean
3. MessageOperations接口是用于注入的自定义接口

在这种情况下，明显的变化是：

interface MessageOperations {
SseEmitter associateSseEmitterWithUser(String userName); 
}
@Service
public class MessageTemplate implements MessageOperations {
private Map<String, SseEmitter> sses = new ConcurrentHashMap<>();
// other existing code you might already have

public SseEmitter associateSseEmitterWithUser(String username) {
SseEmitter sseEmitter = new SseEmitter(3600000L);
sses.put(username, sseEmitter);
return sseEmitter;
}
}
@Controller 
@RequestMapping(value = “/“)
public class MessageController {
@Autowired MessageOperations mesgOps;

@GetMapping(value=“/conn/{username})
public SseEmitter openConn(@PathVariable(“username”) String   username) {
return mesgOps.associateSseEmitterWithUser(username); 
}  
}