请创建 android websocket 代码

以下是一个简单的Android WebSocket示例：

首先，在Android项目中添加以下依赖项：

implementation 'org.java-websocket:Java-WebSocket:1.4.0'

然后，创建一个WebSocket客户端类：

public class WebSocketClient extends Thread {
    private final URI uri;
    private WebSocket mWebSocket;
    private boolean isConnected = false;

    public WebSocketClient(String url) throws URISyntaxException {
        uri = new URI(url);
    }

    @Override
    public void run() {
        super.run();
        connectWebSocket();
    }

    private void connectWebSocket() {
        WebSocketFactory factory = new WebSocketFactory();
        try {
            mWebSocket = factory.createSocket(uri);
        } catch (IOException e) {
            e.printStackTrace();
        }
        mWebSocket.addListener(new WebSocketAdapter() {
            @Override
            public void onConnected(WebSocket websocket, Map<String, List<String>> headers) throws Exception {
                super.onConnected(websocket, headers);
                isConnected = true;
                Log.d("WebSocket", "Connected to server");
            }

            @Override
            public void onTextMessage(WebSocket websocket, String message) throws Exception {
                super.onTextMessage(websocket, message);
                Log.d("WebSocket", "Received message: " + message);
            }

            @Override
            public void onClose(WebSocket websocket, int code, String reason, boolean remote) throws Exception {
                super.onClose(websocket, code, reason, remote);
                isConnected = false;
                Log.d("WebSocket", "Disconnected from server");
            }
        });

        try {
            mWebSocket.connect();
        } catch (WebSocketException e) {
            e.printStackTrace();
        }
    }

    public void sendMessage(String message) {
        if (isConnected && mWebSocket.isOpen()) {
            mWebSocket.sendText(message);
            Log.d("WebSocket", "Sent message: " + message);
        }
    }

    public void disconnect() {
        if (isConnected && mWebSocket.isOpen()) {
            mWebSocket.disconnect();
        }
    }
}

接下来，在Activity中使用WebSocketClient：

public class MainActivity extends AppCompatActivity {
    private WebSocketClient mWebSocketClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        try {
            mWebSocketClient = new WebSocketClient("ws://echo.websocket.org");
            mWebSocketClient.start();
        } catch (URISyntaxException e) {
            e.printStackTrace();
        }

        Button sendButton = findViewById(R.id.send_button);
        final EditText messageEditText = findViewById(R.id.message_edittext);

        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String message = messageEditText.getText().toString();
                mWebSocketClient.sendMessage(message);
            }
        });
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mWebSocketClient.disconnect();
    }
}

在此示例中，我们使用了echo.websocket.org作为WebSocket服务器。您可以替换为自己的WebSocket服务器URL。sendMessage()方法用于向服务器发送消息。disconnect()方法用于断开WebSocket连接。