java - 使用 java 程序连接到我的 google 驱动器的函数中传递的值应该是什么？

Question

我从谷歌开发者网站获得以下代码:

package javaapplication24;
import com.google.api.client.http.GenericUrl;
import com.google.api.client.http.HttpResponse;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.model.File;

import java.io.IOException;
import java.io.InputStream;

// ...

public class NewClass {

// ...

/**
* Print a file's metadata.
*
 * @param args
* @param service Drive API service instance.
* @param fileId ID of the file to print metadata for.
*/

private static void printFile(Drive service, String fileId) {


try {
  File file = service.files().get(fileId).execute();

  System.out.println("Title: " + file.getTitle());
  System.out.println("Description: " + file.getDescription());
  System.out.println("MIME type: " + file.getMimeType());
} catch (IOException e) {
  System.out.println("An error occured: " + e);
}
}

/**
 * Download a file's content.
 *
 * @param service Drive API service instance.
 * @param file Drive File instance.
 * @return InputStream containing the file's content if successful,
 *         {@code null} otherwise.
 */
private static InputStream downloadFile(File file, Drive service) {
if (file.getDownloadUrl() != null && file.getDownloadUrl().length() > 0) {
  try {
    HttpResponse resp =
        service.getRequestFactory().buildGetRequest(new GenericUrl(file.getDownloadUrl()))
            .execute();
    return resp.getContent();
  } catch (IOException e) {
    // An error occurred.
    e.printStackTrace();
    return null;
  }
} else {
  // The file doesn't have any content stored on Drive.
  return null;
}
}

// ...
}

我知道我需要用它编写一个主函数并调用函数 printFile 和 DownloadFile 但我没有得到要在函数中作为变量服务传递的内容？

Answer 1

你必须先了解它是如何工作的!

1. 为了下载或打印有关文件的详细信息，您需要通过具有正确范围(只读、修改/删除等权限)的 Google 帐户对您的应用进行身份验证。
2. 身份验证完成后。您将获得访问 token 来访问数据。

这是一小段代码，说明了云端硬盘服务的含义

     /**
     * Build and return an authorized Drive client service.
     * @return an authorized Drive client service
     * @throws IOException
     */
    public static Drive getDriveService() throws IOException {
        Credential credential = authorize();
        return new Drive.Builder(
                HTTP_TRANSPORT, JSON_FACTORY, credential)
                .setApplicationName(APPLICATION_NAME)
                .build();
    }

前往此链接了解更多信息

https://developers.google.com/drive/web/quickstart/java

注意:如果我将完整的代码复制粘贴到此处，这将是不必要的长答案