public class Blob extends BlobInfoAn object in Google Cloud Storage. A Blob object includes the BlobId instance,
the set of properties inherited from the BlobInfo class and the Storage instance.
The class provides methods to perform operations on the object. Reading a property value does not
issue any RPC calls. The object content is not stored within the Blob instance.
Operations that access the content issue one or multiple RPC calls, depending on the content
size.
Objects of this class are immutable. Operations that modify the blob like #update and
#copyTo return a new object. Any changes to the object in Google Cloud Storage made after
creation of the Blob are not visible in the Blob. To get a Blob object
with the most recent information use #reload.
Example of getting the content of the object in Google Cloud Storage:
BlobId blobId = BlobId.of(bucketName, blobName);
Blob blob = storage.get(blobId);
long size = blob.getSize(); // no RPC call is required
byte[] content = blob.getContent(); // one or multiple RPC calls will be issued