Listing just the sub folders in an s3 bucket

Question

I have an s3 structure as follows:

s3bucketname -> List of first level keys -> List of second level keys -> List of third level keys -> Actual fi         


        

Answer 1

I did the following code which seems to work fine, you have to pass a prefix and make sure the prefix ends with /, and also specify the delimiter you want to get your list of sub-directories. The following should work:

public List listKeysInDirectory(String bucketName, String prefix) {
    String delimiter = "/";
    if (!prefix.endsWith(delimiter)) {
        prefix += delimiter;
    }

    ListObjectsRequest listObjectsRequest = new ListObjectsRequest()
            .withBucketName(bucketName).withPrefix(prefix)
            .withDelimiter(delimiter);
    ObjectListing objects = _client.listObjects(listObjectsRequest);
    return objects.getCommonPrefixes();
}