DoubleCloud.org

Amazon released its SDK for Java last month. It’s a complete set of APIs that cover almost all the services from EC2, S3, SQS, RDS to SimpleDB. Overall Amazon has done a consistent job, but the SDK is NOT really object oriented. And that I think is critical for higher development productivity. 

Structure of the SDK

Before explaining why it’s not quite there, let’s take a look at the structure of the API itself. The SDK includes many packages. For each service, you find two or three packages: basic, model, and possibly util package.

In each of the basic packages you can find the two interfaces, and two implementation classes. Let’s pick EC2 as a sample here. The AmazonEC2 and AmazonEC2Async are two interfaces and implemented by AmazonEC2Client and AmazonEC2AsyncClient respectively. More methods are defined in the synchronous than the asynchronous versions with the majority of them overlapping with similar method names.

AllocateAddressResult allocateAddress()
AllocateAddressResult allocateAddress(AllocateAddressRequest allocateAddressRequest)
Future<AllocateAddressResult> allocateAddressAsync(AllocateAddressRequest allocateAddressRequest)

The first two versions wait and get you results upon return. The third version doesn’t wait and gets the result later.  Read more... (731 words, estimated 2:55 mins reading time)