The AWS SDK for Java 1.x has entered maintenance mode as of July 31, 2024,
and will reach end-of-support
Enabling Long Polling for Amazon SQS Message Queues
Amazon SQS uses short polling by default, querying only a subset of the servers—based on a weighted random distribution—to determine whether any messages are available for inclusion in the response.
Long polling helps reduce your cost of using Amazon SQS by reducing the number of empty responses when there are no messages available to return in reply to a ReceiveMessage request sent to an Amazon SQS queue and eliminating false empty responses.
Note
You can set a long polling frequency from 1-20 seconds.
Enabling Long Polling when Creating a Queue
To enable long polling when creating an Amazon SQS queue, set the ReceiveMessageWaitTimeSeconds
attribute on the CreateQueueRequest object before calling the AmazonSQS class' createQueue
method.
Imports
import com.amazonaws.services.sqs.AmazonSQS; import com.amazonaws.services.sqs.AmazonSQSClientBuilder; import com.amazonaws.services.sqs.model.AmazonSQSException; import com.amazonaws.services.sqs.model.CreateQueueRequest;
Code
final AmazonSQS sqs = AmazonSQSClientBuilder.defaultClient(); // Enable long polling when creating a queue CreateQueueRequest create_request = new CreateQueueRequest() .withQueueName(queue_name) .addAttributesEntry("ReceiveMessageWaitTimeSeconds", "20"); try { sqs.createQueue(create_request); } catch (AmazonSQSException e) { if (!e.getErrorCode().equals("QueueAlreadyExists")) { throw e; } }
See the complete example
Enabling Long Polling on an Existing Queue
In addition to enabling long polling when creating a queue, you can also enable it on an existing queue by setting ReceiveMessageWaitTimeSeconds
on the SetQueueAttributesRequest before calling the AmazonSQS class' setQueueAttributes
method.
Imports
import com.amazonaws.services.sqs.model.SetQueueAttributesRequest;
Code
SetQueueAttributesRequest set_attrs_request = new SetQueueAttributesRequest() .withQueueUrl(queue_url) .addAttributesEntry("ReceiveMessageWaitTimeSeconds", "20"); sqs.setQueueAttributes(set_attrs_request);
See the complete example
Enabling Long Polling on Message Receipt
You can enable long polling when receiving a message by setting the wait time in seconds on the ReceiveMessageRequest that you supply to the AmazonSQS class' receiveMessage
method.
Note
You should make sure that the AWS client’s request timeout is larger than the maximum long poll time (20s) so that your receiveMessage
requests don’t time out while waiting for the next poll event!
Imports
import com.amazonaws.services.sqs.model.ReceiveMessageRequest;
Code
ReceiveMessageRequest receive_request = new ReceiveMessageRequest() .withQueueUrl(queue_url) .withWaitTimeSeconds(20); sqs.receiveMessage(receive_request);
See the complete example
More Info
-
Amazon SQS Long Polling in the Amazon SQS Developer Guide
-
CreateQueue in the Amazon SQS API Reference
-
ReceiveMessage in the Amazon SQS API Reference
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SetQueueAttributes in the Amazon SQS API Reference