要使用Kafka Connect实现从WebSocket流到Kafka的数据传输，我们需要创建一个自定义连接器。以下是实现此过程的步骤。

1.创建连接器插件

为了实现自定义的WebSocket连接器，我们需要扩展Kafka Connect中的SourceConnector类，并实现start()，poll()和stop()方法。

下面是一个最小化的WebSocket连接器插件示例：

public class CustomWebSocketConnector extends SourceConnector {

  private WebSocketClient client;
  private CustomWebSocketHandler handler;
  private String topic;
  private String socketUrl;

  @Override
  public String version() {
    return "0.1";
  }

  @Override
  public void start(Map props) throws ConnectException {
    topic = props.get("topic");
    socketUrl = props.get("socket.url");

    client = new WebSocketClient();
    handler = new CustomWebSocketHandler(context, topic);

    try {
      client.start();
      client.connect(handler, new URI(socketUrl));
    } catch (Exception e) {
      throw new ConnectException(e);
    }
  }

  @Override
  public List> poll() throws InterruptedException {
    handler.await();

    List> records = handler.getRecords();
    handler.clearRecords();

    return records;
  }

  @Override
  public void stop() throws ConnectException {
    try {
      client.stop();
    } catch (Exception e) {
      throw new ConnectException(e);
    }
  }

}

2.创建WebSocket处理程序

在我们的自定义连接器插件中，我们使用了一个名为CustomWebSocketHandler的辅助类来处理WebSocket消息，将其转换为Kafka记录，然后将记录发送到Kafka主题。

下面是CustomWebSocketHandler示例：

public class CustomWebSocketHandler extends WebSocketAdapter {

  private static final Logger log = LoggerFactory.getLogger(CustomWebSocketHandler.class);

  private final KafkaProducer producer;
  private final List> records;
  private final String topic;

  public CustomWebSocketHandler(ConnectorContext context, String topic) {
    this.producer = context.kafka