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# WebSocket Support
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WebSocket protocol support for real-time bidirectional communication.
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## WebSocket Interface
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```kotlin { .api }
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interface WebSocket {
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    fun request(): Request
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    fun queueSize(): Long
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    fun send(text: String): Boolean
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    fun send(bytes: ByteString): Boolean
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    fun close(code: Int, reason: String?): Boolean
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    fun cancel()
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}
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```
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## WebSocketListener
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```kotlin { .api }
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abstract class WebSocketListener {
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    open fun onOpen(webSocket: WebSocket, response: Response) {}
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    open fun onMessage(webSocket: WebSocket, text: String) {}
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    open fun onMessage(webSocket: WebSocket, bytes: ByteString) {}
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    open fun onClosing(webSocket: WebSocket, code: Int, reason: String) {}
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    open fun onClosed(webSocket: WebSocket, code: Int, reason: String) {}
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    open fun onFailure(webSocket: WebSocket, t: Throwable, response: Response?) {}
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}
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```
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### WebSocket Example
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```kotlin
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val listener = object : WebSocketListener() {
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    override fun onMessage(webSocket: WebSocket, text: String) {
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        println("Received: $text")
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    }
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}
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val request = Request.Builder().url("wss://echo.websocket.org").build()
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val webSocket = client.newWebSocket(request, listener)
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webSocket.send("Hello WebSocket!")
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```