请以stream: true和长连接 的方式写一个方法，能直接被外部传参进行访问的实现。

以下是一个使用 stream: true 和长连接方式的方法示例，可以通过传递参数进行访问：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class OpenAIJavaExample {
    public static void main(String[] args) {
        try {
            String apiKey = "YOUR_API_KEY";
            String prompt = "Hello, world!";
            String model = "gpt-3.5-turbo";
            int maxTokens = 10;

            String response = OpenAIJavaExample.sendRequest(apiKey, prompt, model, maxTokens);

            System.out.println("Response: " + response);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static String sendRequest(String apiKey, String prompt, String model, int maxTokens) throws IOException {
        String url = "https://api.openai.com/v1/engines/" + model + "/completions";
        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();

        // Set the request method and headers
        con.setRequestMethod("POST");
        con.setRequestProperty("Content-Type", "application/json");
        con.setRequestProperty("Authorization", "Bearer " + apiKey);

        // Build the JSON request body
        String requestBody = "{\"prompt\": \"" + prompt + "\", \"max_tokens\": " + maxTokens + ", \"stream\": true}";
        con.setDoOutput(true);
        try (OutputStream os = con.getOutputStream()) {
            byte[] input = requestBody.getBytes("utf-8");
            os.write(input, 0, input.length);
        }

        // Send the request and get the response
        int responseCode = con.getResponseCode();
        BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuilder response = new StringBuilder();
        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        return response.toString();
    }
}

您可以将此代码放在一个类中，并通过传递参数调用 `sendRequest` 方法来访问 OpenAI API。请记得将 `YOUR_API_KEY` 替换为您自己的 API 密钥，并根据需要修改其他参数。