Java WebSocket Server: Understanding the @ServerEndpoint Annotation

The 'ServerEndpoint' annotation is used in Java to mark a class as a WebSocket endpoint on the server side. This annotation is used in conjunction with the 'javax.websocket' package to create a WebSocket server that can handle incoming WebSocket connections and messages.

When a class is annotated with 'ServerEndpoint', it must have at least one method annotated with 'OnOpen', 'OnMessage', 'OnClose', or 'OnError'. These methods handle incoming WebSocket events such as connection opening, message receiving, connection closing, and error handling.

The 'ServerEndpoint' annotation also allows you to specify the URI path for the WebSocket endpoint, which is the URL that clients will use to connect to the server. For example, 'ServerEndpoint(/mywebsocket)' would create a WebSocket endpoint at the URL 'ws://localhost:8080/myapp/mywebsocket'.

Overall, the 'ServerEndpoint' annotation is a key component in creating a WebSocket server in Java. It allows you to easily define and handle incoming WebSocket connections and messages on the server side.