Simple Queue Service: In Depth

Amazon SQS (aws-sqs) is an easy queuing service with which you can easily send or receive 1-10 messages at a time. SQS support has been in jclouds since version 1.5.0.

Creating a queue

You can lookup a queue by name or create one on demand. Here's a common pattern for that:

URI queue = queueApi.get(queueName);
if (queue == null) {
  queue = queueApi.create(queueName);
}

Getting an api connection to a queue

In SQS, once you discover or create a queue, you can focus a connection to to that, by supplying the queue's url.

queueApi = context.getApi().getMessageApiForQueue(queueURI);

sending a message

Sending a message is simple, just supply the text you wish to send.

queueApi.send("my message");

receiving a message

Receiving a message is also simple: invoke receive and if your result is not null, you have a message!

message = queueApi.receive();

sending many messages

You can check whether bulk message requests came back, by checking the status result

BatchResult<MessageIdAndMD5> acks = api.send(ImmutableMap.<String, String> builder()
        .put("id1", "test message one")
        .put("id2", "test message two")
        .put("id3", "test message two")
        .build());

receiving many messages

Note that you can receive the same message twice even in the same request!. Hence we use List, not Set.

List<Message> messages = api.receive(10);