解决springboot启动报Failed to start bean ‘subProtocolWebSocketHandler‘；

问题发现

使用springboot整合websocket，启动时报错，示例代码：

@EnableWebSocket
@Configuration
public class WebSocketConfig implements WebSocketConfigurer {@Overridepublic void registerWebSocketHandlers(WebSocketHandlerRegistry webSocketHandlerRegistry) {webSocketHandlerRegistry.addHandler(myWebSocketHandler(),"/ws").addInterceptors(new MyHandshakeInterceptor());}@Beanpublic WebSocketHandler myWebSocketHandler() {return new MyWebSocketHandler();}@Beanpublic ServletServerContainerFactoryBean createWebSocketContainer() {ServletServerContainerFactoryBean container = new ServletServerContainerFactoryBean();container.setMaxBinaryMessageBufferSize(8192); // 设置二进制消息缓冲区大小container.setMaxTextMessageBufferSize(8192); // 设置文本消息缓冲区大小container.setAsyncSendTimeout(5000l); // 设置异步发送超时时间（毫秒）// 其他配置项...return container;}
}

public class MyWebSocketHandler extends TextWebSocketHandler {@Overrideprotected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {// 处理接收到的文本消息String payload = message.getPayload();System.out.println("接收到消息：" + payload);// 发送响应消息session.sendMessage(new TextMessage("Hello, client!"));}@Overridepublic void afterConnectionEstablished(WebSocketSession session) throws Exception {// WebSocket 连接建立时执行的操作System.out.println("WebSocket 连接已建立");}@Overridepublic void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {// WebSocket 连接关闭时执行的操作System.out.println("WebSocket 连接已关闭");}
}
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketBrokerConfigurer implements WebSocketMessageBrokerConfigurer {}

如图所示：

问题解决

在上述代码中可以看到有两个注解，@EnableWebSocketMessageBroker 和 @EnableWebSocket，同时使用，导致配置错误引起的。由于这两个注解都启用了 WebSocket 功能，因此同时使用它们可能会导致冲突。

两者取其一即可，我们将@EnableWebSocketMessageBroker 删掉，暂时不用基于消息代理。重新启动后，如图：