public void setRequestCredentialsProvider(AWSCredentialsProvider credentialsProvider) {
        this.credentialsProvider = credentialsProvider;
    }
Sets the optional credentials provider to use for this request, overriding the default credentials
provider at the client level.

@param credentialsProvider
           The optional AWS security credentials provider to use for this request, overriding the
           default credentials provider at the client level.
aws-java-sdk-core/src/main/java/com/amazonaws/AmazonWebServiceRequest.java