How to retrieve a segmented List of Containers using the new Java v12 SDK for Azure Blob Storage?

Question

I see that the .NET examples have a ListContainersSegmented API call.

The Java SDK documentation specifies a listBlobContainers call but there is no mention about when it hits the limit of containers it will return per call. Is there a different way to obtain the NextMarker or ContinuationToken for this call?

Do you have any other concerns? – Jim Xu Jul 28 '20 at 00:53 — Jim Xu, Jul 28 '20 at 00:53
@JimXu This is good. Thank you – Somansh Reddy Jul 28 '20 at 18:48 — Somansh Reddy, Jul 28 '20 at 18:48

score 2 · Accepted Answer · answered Jul 24 '20 at 06:58

When we use the method listBlobContainers to list containers, It will paginate if its number is greater than 5000. We also can use ListBlobContainersOptions to define per page size. For more details, please refer to here and here

for example

String endpoint = String.format(Locale.ROOT, "https://%s.blob.core.windows.net", accountName);
        StorageSharedKeyCredential credential = new StorageSharedKeyCredential(accountName, accountKey);
        BlobServiceClient blobServiceClient = new BlobServiceClientBuilder()
                .endpoint(endpoint)
                .credential(credential)
                .buildClient();
        ListBlobContainersOptions options = new ListBlobContainersOptions();
        options.setMaxResultsPerPage(5);
        PagedIterable<BlobContainerItem> pagedIterableResponse= blobServiceClient.listBlobContainers(options, null);
        Iterator<PagedResponse<BlobContainerItem>> ite = pagedIterableResponse.iterableByPage().iterator();
        int i =1;
        while(ite.hasNext()){
            PagedResponse<BlobContainerItem> items= ite.next();
            System.out.println("The containers in the page "+i);
            i++;
            for (BlobContainerItem item: items.getValue()
                 ) {

                   System.out.println("\t"+item.getName());
            }

        }

score 0 · Answer 2 · answered Sep 04 '20 at 07:53

We can use the following method to get the continuation token

        List<BlobItem> allBlobs = new ArrayList<>();
        String continuationToken;
        ListBlobsOptions options = new ListBlobsOptions().setMaxResultsPerPage(5);
        Iterator<PagedResponse<BlobItem>> response = containerClient.listBlobs(options, Duration.ofSeconds(30)).iterableByPage().iterator();
        do {
            PagedResponse<BlobItem> pagedResponse = response.next();
            List<BlobItem> blobs = pagedResponse.getValue();
            continuationToken = pagedResponse.getContinuationToken();
            blobs.forEach(b -> System.out.println(b.getName()));
            allBlobs.addAll(blobs);
        } while (continuationToken != null);

How to retrieve a segmented List of Containers using the new Java v12 SDK for Azure Blob Storage?

2 Answers2