How to send message to WebSocket client from Spring WebSocket server using STOMP?

I have two Spring Boot WebSocket applications using STOMP:

1. WebSocket server
2. WebSocket client

I am able to send a WebSocket message from the client and respond to it from the server. However, now I would like to send a WebSocket message to the client triggered by an event on the server side.

Can someone tell me a way to do this?

Here is what I have now on the server side:

WebSocketConfig.java:

@Configuration @EnableWebSocketMessageBroker public class WebSocketConfig implements WebSocketMessageBrokerConfigurer { @Override public void configureMessageBroker(MessageBrokerRegistry config) { config.enableSimpleBroker("/topic/"); config.setApplicationDestinationPrefixes("/app"); } @Override public void registerStompEndpoints(StompEndpointRegistry registry) { registry.addEndpoint("/alarm"); } } 

WebSocketController.java:

@Controller public class WebSocketController { @MessageMapping("/alarm") @SendTo("/topic/message") public void processMessageFromClient(@Payload String message, Principal principal) throws Exception { System.out.println("WEBSOCKET MESSAGE RECEIVED" + message); } @RequestMapping(value = "/start/{alarmName}", method = RequestMethod.POST) public String start(@PathVariable String alarmName) throws Exception { System.out.println("Starting " + alarmName); /* SEND MESSAGE TO WEBSOCKET CLIENT HERE */ return "redirect:/"; } }