In this tutorial, we will see how to create SQS Standard and FIFO Queues using AWS Java SDK.

AWS SQS:

AWS SQS is actually the first-ever AWS service publicly available, so it’s one of the oldest services they have.

SQS basically a message queue service, so it gives you access to a message queue, which can be used to store messages while an application or a computer process them.

SQS Queue:

A queue is a temporary repository for messages which are waiting for processing.

Types of Queues:

There are 2 different types of SQS Queue available, the main difference between the two is how they handle the ordering messages.

<dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>sqs</artifactId>
</dependency>

 % mvn clean install
[INFO] Scanning for projects...
[INFO] 
[INFO] -------------------< AWS_EXample:java-aws-examples >--------------------
[INFO] Building java-aws-examples 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
...
..

package com.otp;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.CreateQueueRequest;
import software.amazon.awssdk.services.sqs.model.GetQueueUrlResponse;
import software.amazon.awssdk.services.sqs.model.GetQueueUrlRequest;
import software.amazon.awssdk.services.sqs.model.SqsException;

import java.util.List;

public class SQS_Example {

    public static void main(String[] args) {
        String queueName = "My-Sample-Queue";
        SqsClient sqsClient = SqsClient.builder()
                .region(Region.US_WEST_2)
                .build();
        String queueUrl= createQueue(sqsClient, queueName);
        System.out.println("Queue URL : "+queueUrl);
        sqsClient.close();
    }

    public static String createQueue(SqsClient sqsClient,String queueName) {
        try {
            CreateQueueRequest cqr = CreateQueueRequest.builder()
                    .queueName(queueName)
                    .build();

            sqsClient.createQueue(cqr);

            GetQueueUrlResponse getQueueUrlResponse =
                    sqsClient.getQueueUrl(GetQueueUrlRequest.builder().queueName(queueName).build());
            return getQueueUrlResponse.queueUrl();
        } catch (SqsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
        return null;
    }
}

Output:

Queue URL : https://sqs.us-west-2.amazonaws.com/12345678/My-Sample-Queue

You can see the first My-Sample-Queue has been created in the AWS console. You can also observe that it is a Standard queue.

Create SQS FIFO Queue:

As we discussed earlier in this tutorial, the FIFO queues are first-in-first-out delivery. So the order in which messages are sent and received is strictly preserved and you get exactly once for processing.

Creatin the FIFO queues using aws java sdkis almost similar to the standard queue, but this time we need to pass the queue attributes to the CreateQueueRequest saying

QueueAttributeName set totrue.

SQS_Example

package com.otp;
import java.util.Map;
import java.util.HashMap;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sqs.SqsClient;
import software.amazon.awssdk.services.sqs.model.*;

public class SQS_Example {

    public static void main(String[] args) {
        SqsClient sqsClient = SqsClient.builder()
                .region(Region.US_WEST_2)
                .build();

        String fifoQueueUrl= createFIFOQueue(sqsClient, "My-FIFO-Queue.fifo");
        System.out.println("fifoQueueUrl : "+fifoQueueUrl);
        sqsClient.close();
    }

    public static String createFIFOQueue(SqsClient sqsClient,String queueName) {
        Map<QueueAttributeName, String> queueAttributes = new HashMap<>();
        queueAttributes.put(QueueAttributeName.FIFO_QUEUE, "true");
        try {
            CreateQueueRequest cqr = CreateQueueRequest.builder()
                    .queueName(queueName)
                    .attributes(queueAttributes)
                    .build();

            sqsClient.createQueue(cqr);

            GetQueueUrlResponse getQueueUrlResponse =
                    sqsClient.getQueueUrl(GetQueueUrlRequest.builder().queueName(queueName).build());
            return getQueueUrlResponse.queueUrl();
        } catch (SqsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
        return "";
    }
}

Output:

fifoQueueUrl : https://sqs.us-west-2.amazonaws.com/123456/My-FIFO-Queue.fifo

List Queues:

Reading all queues.

SQS_Example

package com.otp;

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

public class SQS_Example {

    public static void main(String[] args) {
        SqsClient sqsClient = SqsClient.builder()
                .region(Region.US_WEST_2)
                .build();
        listAllQueues(sqsClient);
        sqsClient.close();
    }
    
    public static void listAllQueues(SqsClient sqsClient) {

        try {
            ListQueuesRequest listQueuesRequest = ListQueuesRequest.builder().build();
            ListQueuesResponse listQueuesResponse = sqsClient.listQueues(listQueuesRequest);

            listQueuesResponse.queueUrls().forEach(System.out::println);

        } catch (SqsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
    }
}

Output:

https://sqs.us-west-2.amazonaws.com/123456/My-FIFO-Queue.fifo
https://sqs.us-west-2.amazonaws.com/123456/My-Sample-Queue

References:

• AWS SQS Queue Architecture
• Install AWS CLI

Download Source From GIT:

Happy Learning 🙂