要使用Android Studio创建一个基于Java的WebSocket客户端和服务器，可以按照以下步骤进行操作：

1. 打开Android Studio，并创建一个新的空白项目。
2. 在项目的app模块下的build.gradle文件中添加以下依赖项：

implementation 'org.java-websocket:Java-WebSocket:1.5.1'

3. 在MainActivity.java文件中添加以下代码来实现WebSocket客户端：

import org.java_websocket.client.WebSocketClient;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
import java.net.URISyntaxException;

public class MainActivity extends AppCompatActivity {

    WebSocketClient mWebSocketClient;

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

        connectWebSocket();
    }

    private void connectWebSocket() {
        URI uri;
        try {
            uri = new URI("ws://your_server_url");
        } catch (URISyntaxException e) {
            e.printStackTrace();
            return;
        }

        mWebSocketClient = new WebSocketClient(uri) {
            @Override
            public void onOpen(ServerHandshake serverHandshake) {
                Log.i("WebSocket", "Opened");
                mWebSocketClient.send("Hello, Server!");
            }

            @Override
            public void onMessage(String s) {
                final String message = s;
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        // 处理接收到的消息
                    }
                });
            }

            @Override
            public void onClose(int i, String s, boolean b) {
                Log.i("WebSocket", "Closed " + s);
            }

            @Override
            public void onError(Exception e) {
                Log.i("WebSocket", "Error " + e.getMessage());
            }
        };

        mWebSocketClient.connect();
    }
}

4. 要实现WebSocket服务器，可以创建一个新的Java类，例如WebSocketServer.java，并添加以下代码：

import org.java_websocket.WebSocket;
import org.java_websocket.handshake.ClientHandshake;
import org.java_websocket.server.WebSocketServer;
import java.net.InetSocketAddress;

public class WebSocketServerExample extends WebSocketServer {

    public WebSocketServerExample(int port) {
        super(new InetSocketAddress(port));
    }

    @Override
    public void onOpen(WebSocket conn, ClientHandshake handshake) {
        conn.send("Welcome to the server!");
        broadcast("new connection: " + handshake.getResourceDescriptor());
        System.out.println("new connection to " + conn.getRemoteSocketAddress());
    }

    @Override
    public void onClose(WebSocket conn, int code, String reason, boolean remote) {
        System.out.println("closed " + conn.getRemoteSocketAddress() + " with exit code " + code + " additional info: " + reason);
    }

    @Override
    public void onMessage(WebSocket conn, String message) {
        System.out.println("received message from " + conn.getRemoteSocketAddress() + ": " + message);
    }

    @Override
    public void onError(WebSocket conn, Exception ex) {
        System.err.println("an error occurred on connection " + conn.getRemoteSocketAddress() + ":" + ex);
    }

    public static void main(String[] args) {
        int port = 8887; // 端口号
        WebSocketServerExample server = new WebSocketServerExample(port);
        server.start();
        System.out.println("WebSocket server started on port: " + server.getPort());
    }
}

请注意，这只是一个简单的示例，你可以根据你的需求进行相应的更改和扩展。

这样，你就可以使用Android Studio创建一个基于Java的WebSocket客户端和服务器了。