Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Send, receive, and delete Amazon Simple Queue Service messages

A message is a piece of data that can be sent and received by distributed components. Messages are always delivered using an SQS Queue.

The sqsClient variable that is used in the following examples can be created from the following snippet.

SqsClient sqsClient = SqsClient.create();

When you create an SqsClient by using the static create() method, the SDK configures the Region by using the default region provider chain and the credentials by using the default credentials provider chain.

Send a message

Add a single message to an Amazon Simple Queue Service queue by calling the SqsClient client sendMessage method. Provide a SendMessageRequest object that contains the queue’s URL, message body, and optional delay value (in seconds).

Imports

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.*;
import java.util.List;

Code

            sqsClient.sendMessage(SendMessageRequest.builder()
                .queueUrl(queueUrl)
                .messageBody("Hello world!")
                .delaySeconds(10)
                .build());

            sqsClient.sendMessage(sendMsgRequest);

Send multiple messages in a request

Send more than one message in a single request by using the SqsClient sendMessageBatch method. This method takes a SendMessageBatchRequest that contains the queue URL and a list of messages to send. (Each message is a SendMessageBatchRequestEntry.) You can also delay sending a specific message by setting a delay value on the message.

Imports

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.*;
import java.util.List;

Code

            SendMessageBatchRequest sendMessageBatchRequest = SendMessageBatchRequest.builder()
                .queueUrl(queueUrl)
                .entries(SendMessageBatchRequestEntry.builder().id("id1").messageBody("Hello from msg 1").build(),
                        SendMessageBatchRequestEntry.builder().id("id2").messageBody("msg 2").delaySeconds(10).build())
                .build();
            sqsClient.sendMessageBatch(sendMessageBatchRequest);

See the complete sample on GitHub.

Retrieve Messages

Retrieve any messages that are currently in the queue by calling the SqsClient receiveMessage method. This method takes a ReceiveMessageRequest that contains the queue URL. You can also specify the maximum number of messages to return. Messages are returned as a list of Message objects.

Imports

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.*;
import java.util.List;

Code

        try {
            ReceiveMessageRequest receiveMessageRequest = ReceiveMessageRequest.builder()
                .queueUrl(queueUrl)
                .maxNumberOfMessages(5)
                .build();
            List<Message> messages = sqsClient.receiveMessage(receiveMessageRequest).messages();
            return messages;
        } catch (SqsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
        return null;

See the complete sample on GitHub.

Delete a message after receipt

After receiving a message and processing its contents, delete the message from the queue by sending the message's receipt handle and queue URL to the SqsClient's deleteMessage method.

Imports

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.*;
import java.util.List;

Code

        try {
            for (Message message : messages) {
                DeleteMessageRequest deleteMessageRequest = DeleteMessageRequest.builder()
                        .queueUrl(queueUrl)
                        .receiptHandle(message.receiptHandle())
                        .build();
                sqsClient.deleteMessage(deleteMessageRequest);
            }

See the complete sample on GitHub.

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