Package jakarta.websocket.server

Annotation Interface ServerEndpoint

@Retention(RUNTIME) @Target(TYPE) public @interface ServerEndpoint
This class level annotation declares that the class it decorates is a web socket endpoint that will be deployed and made available in the URI-space of a web socket server. The annotation allows the developer to define the URL (or URI template) which this endpoint will be published, and other important properties of the endpoint to the websocket runtime, such as the encoders it uses to send messages.

The annotated class must have a public no-arg constructor.

For example: 

 
 @ServerEndpoint("/hello");
 public class HelloServer {

     @OnMessage
     public void processGreeting(String message, Session session) {
         System.out.println("Greeting received:" + message);
     }

 }

  • Required Element Summary

    Required Elements
    Modifier and Type
    Required Element
    Description
    String
    value
    The URI or URI-template, level-1 (See RFC 6570) where the endpoint will be deployed.

  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    Class<? extends ServerEndpointConfig.Configurator>
    configurator
    The optional custom configurator class that the developer would like to use to further configure new instances of this endpoint.
    Class<? extends Decoder>[]
    decoders
    The ordered array of decoder classes this endpoint will use.
    Class<? extends Encoder>[]
    encoders
    The ordered array of encoder classes this endpoint will use.
    String[]
    subprotocols
    The ordered array of web socket protocols this endpoint supports.

  • Element Details

    • value

      String value
      The URI or URI-template, level-1 (See RFC 6570) where the endpoint will be deployed. The URI us relative to the root of the web socket container and must begin with a leading "/". Trailing "/"'s are ignored. Examples: 
       
 @ServerEndpoint("/chat")
 @ServerEndpoint("/chat/{user}")
 @ServerEndpoint("/booking/{privilege-level}")
      Returns:
      the URI or URI-template

    • subprotocols

      String[] subprotocols
      The ordered array of web socket protocols this endpoint supports. For example, {"superchat", "chat"}.
      Returns:
      the subprotocols.
      Default:
      {}

    • decoders

      Class<? extends Decoder>[] decoders
      The ordered array of decoder classes this endpoint will use. For example, if the developer has provided a MysteryObject decoder, this endpoint will be able to receive MysteryObjects as web socket messages. The websocket runtime will use the first decoder in the list able to decode a message, ignoring the remaining decoders.
      Returns:
      the decoders.
      Default:
      {}

    • encoders

      Class<? extends Encoder>[] encoders
      The ordered array of encoder classes this endpoint will use. For example, if the developer has provided a MysteryObject encoder, this class will be able to send web socket messages in the form of MysteryObjects. The websocket runtime will use the first encoder in the list able to encode a message, ignoring the remaining encoders.
      Returns:
      the encoders.
      Default:
      {}

    • configurator

      Class<? extends ServerEndpointConfig.Configurator> configurator
      The optional custom configurator class that the developer would like to use to further configure new instances of this endpoint. If no configurator class is provided, the implementation uses its own. The implementation creates a new instance of the configurator per logical endpoint.
      Returns:
      the custom configuration class, or ServerEndpointConfig.Configurator.class if none was set in the annotation.
      Default:
      jakarta.websocket.server.ServerEndpointConfig.Configurator.class