Question

我无法将Azure Blob文件下载到本地磁盘。请在下面找到我用来下载文件的Java代码。运行并执行HTTP触发测试时，看不到文件下载到本地路径中。另外，我已经将身份验证授予了公共访问权限。并且，我能够使用blob.downloadText（）读取txt文件的内容。但是我无法将其下载到文件中。

我的要求是将Blob存储中的pdf下载到我的本地磁盘。

 @FunctionName("BlobDownload-Java")
    public void run1(
            @HttpTrigger(name = "req", methods = {HttpMethod.GET, HttpMethod.POST}, authLevel = AuthorizationLevel.FUNCTION) HttpRequestMessage<Optional<String>> request,
            final ExecutionContext context) {
        context.getLogger().info("Java HTTP trigger processed a request.");


        try {
            // Retrieve storage account from connection-string.
            CloudStorageAccount storageAccount = CloudStorageAccount.parse(storageConnectionString);

            // Create the blob client.
            CloudBlobClient blobClient = storageAccount.createCloudBlobClient();

            // Get a reference to a container.
            // The container name must be lower case
            CloudBlobContainer container = blobClient.getContainerReference("doccontainer");


          CloudBlockBlob blob1 = container.getBlockBlobReference("AssembledDoc.pdf");

          context.getLogger().info("File Name Check 1 ----->" +  blob1.getName()); 


          CloudBlockBlob blob2 = container.getBlockBlobReference("Test.txt");
          String s= blob2.downloadText();
          context.getLogger().info("Text Document content ----->" + s );
          File file = new File("C:\\Users\\wb541348\\Project\\Temp.txt");
          blob2.downloadToFile(file.getAbsolutePath());

Answer 1

@Prasanna，您无法将Blob下载到您的本地路径中，因为您的路径模式错误，它应该是“ c：/Users/wb541348/Project/Temp.txt”，还有一点要注意，即需要文件名，这意味着路径不应该只是文件夹，希望它会有所帮助。您也可以单击此sample of azure blob for java sdk以供参考。

Answer 2

如果您只是想将PDF文件下载到本地，这是我的测试代码，可以尝试一下。

@Test
public void downloadBlob(){


    try {
        CloudStorageAccount storageAccount = CloudStorageAccount.parse(storageConnectionString);

        //Create the service client object for credentialed access to the Blob service.
        CloudBlobClient blobClient = storageAccount.createCloudBlobClient();

        // Retrieve a reference to a container.
        CloudBlobContainer container = blobClient.getContainerReference("blobcontainer");


        CloudBlob blob1 =container.getBlockBlobReference("thinking-in-java.pdf");

        blob1.download(new FileOutputStream("C:\\Users\\georgec\\Documents\\" + blob1.getName()));


    } catch (URISyntaxException e) {
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        e.printStackTrace();
    } catch (StorageException e) {
        e.printStackTrace();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } 

}

如果您仍有疑问，请告诉我。

如何下载Azure BLOB？

2 个答案: