public void setOnCompleted(Listener<OutboundBatchTask<R, Result>> value) {
            onCompleted = value;
        }
Task to send a batch of outbound requests to SQS.
<p>
The batch task is constructed open and accepts requests until full, or until
{@code maxBatchOpenMs} elapses. At that point, the batch closes and the collected requests
are assembled into a single batch request to SQS. Specialized for each type of outbound
request.
<p>
Instances of this class (and subclasses) are thread-safe.

@param <R>
           the type of the SQS request to batch
@param <Result>
           the type of result he futures issued by this task will return
aws-java-sdk-sqs/src/main/java/com/amazonaws/services/sqs/buffered/SendQueueBuffer.java