AWS SDK for Java 2.x - Messaging (SQS & SNS)

Overview

Provide comprehensive AWS messaging patterns using AWS SDK for Java 2.x for both SQS and SNS services. Include client setup, queue management, message operations, subscription management, and Spring Boot integration patterns.

When to Use

Use this skill when working with:

Amazon SQS queues for message queuing
SNS topics for event publishing and notification
FIFO queues and standard queues
Dead Letter Queues (DLQ) for message handling
SNS subscriptions with email, SMS, SQS, Lambda endpoints
Pub/sub messaging patterns and event-driven architectures
Spring Boot integration with AWS messaging services
Testing strategies using LocalStack or Testcontainers

Quick Start

Dependencies

xml

<!-- SQS -->
<dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>sqs</artifactId>
</dependency>

<!-- SNS -->
<dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>sns</artifactId>
</dependency>

Basic Client Setup

java

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sns.SnsClient;

SqsClient sqsClient = SqsClient.builder()
    .region(Region.US_EAST_1)
    .build();

SnsClient snsClient = SnsClient.builder()
    .region(Region.US_EAST_1)
    .build();

Examples

Basic SQS Operations

Create and Send Message

java

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

// Setup SQS client
SqsClient sqsClient = SqsClient.builder()
    .region(Region.US_EAST_1)
    .build();

// Create queue
String queueUrl = sqsClient.createQueue(CreateQueueRequest.builder()
    .queueName("my-queue")
    .build()).queueUrl();

// Send message
String messageId = sqsClient.sendMessage(SendMessageRequest.builder()
    .queueUrl(queueUrl)
    .messageBody("Hello, SQS!")
    .build()).messageId();

Receive and Delete Message

java

// Receive messages with long polling
ReceiveMessageResponse response = sqsClient.receiveMessage(ReceiveMessageRequest.builder()
    .queueUrl(queueUrl)
    .maxNumberOfMessages(10)
    .waitTimeSeconds(20)
    .build());

// Process and delete messages
response.messages().forEach(message -> {
    System.out.println("Received: " + message.body());
    sqsClient.deleteMessage(DeleteMessageRequest.builder()
        .queueUrl(queueUrl)
        .receiptHandle(message.receiptHandle())
        .build());
});

Basic SNS Operations

Create Topic and Publish

java

import software.amazon.awssdk.services.sns.SnsClient;
import software.amazon.awssdk.services.sns.model.*;

// Setup SNS client
SnsClient snsClient = SnsClient.builder()
    .region(Region.US_EAST_1)
    .build();

// Create topic
String topicArn = snsClient.createTopic(CreateTopicRequest.builder()
    .name("my-topic")
    .build()).topicArn();

// Publish message
String messageId = snsClient.publish(PublishRequest.builder()
    .topicArn(topicArn)
    .subject("Test Notification")
    .message("Hello, SNS!")
    .build()).messageId();

Advanced Examples

FIFO Queue Pattern

java

// Create FIFO queue
Map<QueueAttributeName, String> attributes = Map.of(
    QueueAttributeName.FIFO_QUEUE, "true",
    QueueAttributeName.CONTENT_BASED_DEDUPLICATION, "true"
);

String fifoQueueUrl = sqsClient.createQueue(CreateQueueRequest.builder()
    .queueName("my-queue.fifo")
    .attributes(attributes)
    .build()).queueUrl();

// Send FIFO message with group ID
String fifoMessageId = sqsClient.sendMessage(SendMessageRequest.builder()
    .queueUrl(fifoQueueUrl)
    .messageBody("Order #12345")
    .messageGroupId("orders")
    .messageDeduplicationId(UUID.randomUUID().toString())
    .build()).messageId();

SNS to SQS Subscription

java

// Create SQS queue for subscription
String subscriptionQueueUrl = sqsClient.createQueue(CreateQueueRequest.builder()
    .queueName("notification-subscriber")
    .build()).queueUrl();

// Get queue ARN
String queueArn = sqsClient.getQueueAttributes(GetQueueAttributesRequest.builder()
    .queueUrl(subscriptionQueueUrl)
    .attributeNames(QueueAttributeName.QUEUE_ARN)
    .build()).attributes().get(QueueAttributeName.QUEUE_ARN);

// Subscribe SQS to SNS
String subscriptionArn = snsClient.subscribe(SubscribeRequest.builder()
    .protocol("sqs")
    .endpoint(queueArn)
    .topicArn(topicArn)
    .build()).subscriptionArn();

Spring Boot Integration Example

java

@Service
@RequiredArgsConstructor
public class OrderNotificationService {

    private final SnsClient snsClient;
    private final ObjectMapper objectMapper;

    @Value("${aws.sns.order-topic-arn}")
    private String orderTopicArn;

    public void sendOrderNotification(Order order) {
        try {
            String jsonMessage = objectMapper.writeValueAsString(order);

            snsClient.publish(PublishRequest.builder()
                .topicArn(orderTopicArn)
                .subject("New Order Received")
                .message(jsonMessage)
                .messageAttributes(Map.of(
                    "orderType", MessageAttributeValue.builder()
                        .dataType("String")
                        .stringValue(order.getType())
                        .build()))
                .build());

        } catch (Exception e) {
            throw new RuntimeException("Failed to send order notification", e);
        }
    }
}

Best Practices

SQS Best Practices

Use long polling: Set
```
waitTimeSeconds
```
(20-40 seconds) to reduce empty responses
Batch operations: Use
```
sendMessageBatch
```
for multiple messages to reduce API calls
Visibility timeout: Set appropriately based on message processing time (default 30 seconds)
Delete messages: Always delete messages after successful processing
Handle duplicates: Implement idempotent processing for retries
Implement DLQ: Route failed messages to dead letter queues for analysis
Monitor queue depth: Use CloudWatch alarms for high queue backlog
Use FIFO queues: When message order and deduplication are critical

SNS Best Practices

Use filter policies: Reduce noise by filtering messages at the source
Message attributes: Add metadata for subscription routing decisions
Retry logic: Handle transient failures with exponential backoff
Monitor failed deliveries: Set up CloudWatch alarms for failed notifications
Security: Use IAM policies for access control and data encryption
FIFO topics: Use when order and deduplication are critical
Avoid large payloads: Keep messages under 256KB for optimal performance

General Guidelines

Region consistency: Use the same region for all AWS resources
Resource naming: Use consistent naming conventions for queues and topics
Error handling: Implement proper exception handling and logging
Testing: Use LocalStack for local development and testing
Documentation: Document subscription endpoints and message formats

Instructions

Setup AWS Credentials

Configure AWS credentials using environment variables, AWS CLI, or IAM roles:

bash

export AWS_ACCESS_KEY_ID=your-access-key
export AWS_SECRET_ACCESS_KEY=your-secret-key
export AWS_REGION=us-east-1

Configure Clients

java

// Basic client configuration
SqsClient sqsClient = SqsClient.builder()
    .region(Region.US_EAST_1)
    .build();

// Advanced client with custom configuration
SnsClient snsClient = SnsClient.builder()
    .region(Region.US_EAST_1)
    .credentialsProvider(DefaultCredentialsProvider.create())
    .httpClient(UrlConnectionHttpClient.create())
    .build();

Implement Message Processing

Connect to SQS/SNS using the AWS SDK clients
Create queues and topics as needed
Send/receive messages with appropriate timeout settings
Process messages in batches for efficiency
Delete messages after successful processing
Handle failures with proper error handling and retries

Integrate with Spring Boot

Configure beans for
```
SqsClient
```
and
```
SnsClient
```
in
```
@Configuration
```
classes
Use
```
@Value
```
to inject queue URLs and topic ARNs from properties
Create service classes with business logic for messaging operations
Implement error handling with
```
@Retryable
```
or custom retry logic
Test integration using Testcontainers or LocalStack

Monitor and Debug

Use AWS CloudWatch for monitoring queue depth and message metrics
Enable AWS SDK logging for debugging client operations
Implement proper logging for message processing activities
Use AWS X-Ray for distributed tracing in production environments

Troubleshooting

Common Issues

Queue does not exist: Verify queue URL and permissions
Message not received: Check visibility timeout and consumer logic
Permission denied: Verify IAM policies and credentials
Connection timeout: Check network connectivity and region configuration
Rate limiting: Implement retry logic with exponential backoff

Performance Optimization

Use long polling to reduce empty responses
Batch message operations to minimize API calls
Adjust visibility timeout based on processing time
Implement connection pooling and reuse clients
Use appropriate message sizes to avoid fragmentation

Detailed References

For comprehensive API documentation and advanced patterns, see:

references/detailed-sqs-operations.md - Complete SQS operations reference
references/detailed-sns-operations.md - Complete SNS operations reference
references/spring-boot-integration.md - Spring Boot integration patterns
references/aws-official-documentation.md - Official AWS documentation and best practices

Constraints and Warnings

Message Size: SQS and SNS messages limited to 256KB
Visibility Timeout: SQS messages become visible again after timeout if not deleted
FIFO Naming: FIFO queues and topics must end with
```
.fifo
```
suffix
FIFO Throughput: FIFO queues have lower throughput limits (300 msg/sec)
Message Retention: SQS messages retained maximum 14 days
Dead Letter Queues: Configure DLQ to prevent message loss
Subscription Limits: SNS topics have limits on number of subscriptions
Filter Policies: SNS filter policies have complexity limits
Cross-Region: SQS queues are region-specific; SNS topics can be cross-region
Cost: Both services charge per API call and data transfer

aws-sdk-java-v2-messaging

NPX Install

Tags

SKILL.md Content

AWS SDK for Java 2.x - Messaging (SQS & SNS)

Overview

When to Use

Quick Start

Dependencies

Basic Client Setup

Examples

Basic SQS Operations

Create and Send Message

Receive and Delete Message

Basic SNS Operations

Create Topic and Publish

Advanced Examples

FIFO Queue Pattern

SNS to SQS Subscription

Spring Boot Integration Example

Best Practices

SQS Best Practices

SNS Best Practices

General Guidelines

Instructions

Setup AWS Credentials

Configure Clients

Implement Message Processing

Integrate with Spring Boot

Monitor and Debug

Troubleshooting

Common Issues

Performance Optimization

Detailed References

Constraints and Warnings