title: Why AmazonSTSCredentialsProvider is only in mobile SDK and not in aws-java-sdk
body: <p>I am working with AWS Assume role access logic. For that I am trying to get new temporary credentials before previous one is expired.</p>
  
  <p>I found AmazonSTSCredentialsProvider is doing this logic. But this is present ony in mobile SDK not in java SDK. Is there any reason that java SDK doesn't have this class or Is Java SDK has some other provider to do this temporary credential refreshment.</p>