App Engine -从云存储下载文件

 ```python

 from google.cloud import storage

 def download_file(bucket_name, source_blob_name, destination_file_name):

     storage_client = storage.Client()

     bucket = storage_client.get_bucket(bucket_name)

     blob = bucket.blob(source_blob_name)

     blob.download_to_filename(destination_file_name)

 # 调用下载函数

 download_file('your-bucket-name', 'path/to/source/blob', 'path/to/destination/file')

 ```

 ```java

 import com.google.cloud.storage.Blob;

 import com.google.cloud.storage.BlobId;

 import com.google.cloud.storage.Storage;

 import com.google.cloud.storage.StorageOptions;

 public class DownloadFile {

     public static void main(String[] args) {

         String bucketName = "your-bucket-name";

         String sourceBlobName = "path/to/source/blob";

         String destinationFileName = "path/to/destination/file";

         Storage storage = StorageOptions.getDefaultInstance().getService();

         Blob blob = storage.get(BlobId.of(bucketName, sourceBlobName));

         blob.downloadTo(Paths.get(destinationFileName));

     }

 }

 ```