# 🌐 Websockets | Pixel Services Docs
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# 🌐 Websockets ​

In this section, we illustrate how to create and manage Websockets in Flash, which are used to establish a bidirectional communication channel between the client and the server.

## Understanding Websockets ​

Websockets are a communication protocol that provides full-duplex communication channels over a single TCP connection. Unlike HTTP, which is a request-response protocol, Websockets allow for real-time, low-latency communication between the client and the server.

Imagine a scenario where you need to send real-time updates to the client, such as a chat application or a live feed: if you were to use HTTP, you would need to poll the server at regular intervals to check for updates, which is inefficient and resource-intensive.

## Creating a Websocket ​

To create a Websocket in Flash, you need to extend the `WebsocketHandler` class and override the `onOpen`, `onMessage`, `onClose`, and `onError` methods. These methods are called when the Websocket connection is opened, a message is received, the connection is closed, and an error occurs, respectively, and they provide you with an instance of the `WebSocketSession` object to be able to interact with it.

java

    public class MyWebsocketHandler extends WebsocketHandler {
        @Override
        public void onOpen(WebSocketSession session) {
            System.out.println("WebSocket connection opened");
        }

        @Override
        public void onClose(WebSocketSession session, int statusCode, String reason) {
            System.out.println("WebSocket connection closed");
        }

        @Override
        public void onMessage(WebSocketSession session, String message) {
            System.out.println("Received message: " + message);

            //optionally send a reponse back to the client
            session.sendMessage("I received your message!");
        }

        @Override
        public void onError(WebSocketSession session, Throwable error) {
            System.out.println("WebSocket error: " + error.getMessage());
        }
    }

To register your Websocket handler with the server, you can use the `server.ws()` method:

java

    public class Example {
        public static void main(String[] args) {
            FlashServer server = new FlashServer(8080);

            server.ws("/ws")
                .register(new MyWebsocketHandler());

            server.start();
        }
    }

## Interacting with Websockets sessions ​

The `WebSocketSession` object provides methods to interact with the Websocket session, such as sending messages, closing the connection, and getting the remote address and session ID.

Method | Params | Description
--- | --- | ---
`getChannel()` | `none` | Returns an instance of `AsynchronousSocketChannel` useful for retrieving info about the client .
`getRequestInfo()` | `none` | Returns an instance of `RequestInfo` containing all sorts of information about the request (headers, method, path etc.) .
`getPath()` | `none` | Returns the path to the websocket endpoint as a `String`.
`getId()` | `none` | Returns the id of the websocket session as a `String`, useful if you want to keep track of the connected clients in a custom manager.
`getBuffer()` | `none` | Returns the ByteBuffer for that session.
`sendMessage()` | `String message` | Sends the `message` to the client as a `String`. it's up to the developer to stringify and de-stringify any data you want to send back and forth
`close()` | `none` | Closes the websocket session.

NOTE

`WebsocketHandler` includes a `setId(String id)` method for overriding the default session ID. Unless you have a specific reason to change it, it's best to leave it as is.

Similarly, the `setBuffer(ByteBuffer buffer)` method allows you to override the default buffer. If you're unsure about this, it's recommended to keep the default setting.