This post briefly demonstrates how to develop and deploy (server and client) Websocket endpoints using the programmatic version of the Java Websocket API
To begin with…
extend the javax.websocket.Endpoint class
Let’s code the client endpoint as well (using the same set of APIs)
.. and then
implement the ServerApplicationConfig interface
It is part of the javax.websocket.server package and can be overridden to implement custom logic for endpoint deployment (for both annotated as well as programmatic endpoints)
What about the client endpoint ?
If required, you can create a your own instance of ClientEndpointConfig and use it while initiating a connection to the websocket server endpoint
To be noted
- Both the client as well as server endpoint config objects are nothing but object (programmatic) equivalents of the elements (value, encoders, decoders, configurator etc.) of the @ServerEndpoint and @ClientEndpoint annotations
- Separate builder classes (ServerEndpointConfig.Builder and ClientEndpointConfig.Builder) were used to create server and client configuration instances respectively
- The creation of a ServerEndpointConfig instance is mandatory since server endpoints cannot be deployed without a URI. This is not the case with client endpoints though – all they do is connect to an existing server endpoint.
- The endpoint config (server & client) have the notion of a configurator which can be created and set via the respective builder methods.
Stay tuned for some more Websocket related action in the near future
feel free to…
- read some of my previous Websocket related posts
- check out the beta version of my (free) mini book: EJB Annotations Primer 🙂