Spring websocket: how intercept the send event through the AbstractSubProtocolEvent hierarchy?

Question

About Spring websocket about intercept Stomp events one approach is extends from the ChannelInterceptorAdapter class

It works how is expected. More details here:

• Spring websocket: how convert easily the Message's payload to POJO in ChannelInterceptorAdapter

Now, according with this tutorial:

• Detecting WebSocket Connects and Disconnects in Spring 4

the approach mentioned above is covered and other approach is work around with ApplicationEvents, it through with:

• SessionConnectEvent
• SessionConnectedEvent
• SessionDisconnectEvent

These classes extends from:

• AbstractSubProtocolEvent

And exists two subclasses more:

• SessionSubscribeEvent
• SessionUnsubscribeEvent

This list is confirmed in (by the same author):

• how to capture connection event in my webSocket server with Spring 4?

The names are by themselves obvious to know what each one does, but just curious

• Why there is no none for the send event?

It to react from:

stompClient.send('/app/ws/something', 
                 {}, 
                 JSON.stringify({'content': $('#content').val()})

For this send event "seems" mandatory work with the ChannelInterceptorAdapter through the postSend(Message<?> message, MessageChannel channel, boolean sent) method yet

Answer 1

The events reflect major points in the lifecycle of a STOMP connection. They're not meant to be notifications for every message sent from the client. For that you can use @MessageMapping methods, or a ChannelInterceptor.