Question

我已经通过java代码在Azure服务器上成功上传了图片，但是当我尝试下载图片时出现异常。

下载代码：

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

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

   // Retrieve reference to a previously created container.
   CloudBlobContainer container = blobClient.getContainerReference("mycontainer");

   // Loop through each blob item in the container.
   for (ListBlobItem blobItem : container.listBlobs()) {
       // If the item is a blob, not a virtual directory.
       if (blobItem instanceof CloudBlob) {
           // Download the item and save it to a file with the same name.
            CloudBlob blob = (CloudBlob) blobItem;
            blob.download(new FileOutputStream("C:\\mydownloads\\" + blob.getName()));
        }
    }
}

获得以下异常，

java.util.NoSuchElementException: An error occurred while enumerating the result, check the original exception for details.
    at com.microsoft.windowsazure.storage.core.LazySegmentedIterator.hasNext(LazySegmentedIterator.java:113)
    at com.test.BlobBasics.main(BlobBasics.java:106)
Caused by: com.microsoft.windowsazure.storage.StorageException: The server encountered an unknown failure: OK
    at com.microsoft.windowsazure.storage.StorageException.translateException(StorageException.java:187)
    at com.microsoft.windowsazure.storage.core.ExecutionEngine.executeWithRetry(ExecutionEngine.java:251)
    at 
    ... 1 more
Caused by: javax.xml.stream.XMLStreamException: ParseError at [row,col]:[1,1]
Message: Content is not allowed in prolog.
    at com.sun.xml.stream.XMLReaderImpl.next(XMLReaderImpl.java:563)
    at com.microsoft.windowsazure.storage.blob.ListBlobsResponse.parseResponse(ListBlobsResponse.java:118)
    at com.microsoft.windowsazure.storage.blob.CloudBlobContainer$6.postProcessResponse(CloudBlobContainer.java:1227)
    at com.microsoft.windowsazure.storage.blob.CloudBlobContainer$6.postProcessResponse(CloudBlobContainer.java:1190)
    at com.microsoft.windowsazure.storage.core.ExecutionEngine.executeWithRetry(ExecutionEngine.java:185)
    ... 2 more

Microsoft description of how to use blob storage in Java

Answer 1

嘿使用下面的代码它会帮助你..

public void downloadAttachment() {
    try {

        final String storageConnectionString = "DefaultEndpointsProtocol=http;" + "AccountName=your account name;" + "AccountKey=your account key";

        // 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
        container = blobClient.getContainerReference("container name");
        if (container.listBlobs() != null) {
            Log.d("in if ", "list conatin value");
            new downloadingAttachment().execute();
        } else {
            Log.d("in else ", "list does not any contain value ");
        }

    } catch (Exception e) {
        // Output the stack trace.
        e.printStackTrace();
    }
}

 public class downloadingAttachment extends AsyncTask<Void, Void, Void> {

    @Override
    protected Void doInBackground(Void... params) {

        Log.d("in if ", "container.listBlobs();" + container.listBlobs());
        Iterable<ListBlobItem> valuesofConatainer = container.listBlobs();
        Log.d("in if ", "valuesofConatainer=" + valuesofConatainer);

        for (ListBlobItem blobItem : container.listBlobs()) {
            // If the item is a blob, not a virtual directory.

            if (blobItem instanceof CloudBlob) {
                // Download the item and save it to a file with the same name.
                CloudBlob blob = (CloudBlob) blobItem;
                try {
                    blob.download(new FileOutputStream("your storage location" + blob.getName() + ".jpeg"));
                    Log.d(" blob.getName()=", " " + blob.getName());
                    break;

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


        return null;
    }
}

无法使用java代码从azure服务器下载图像

1 个答案: