@Override
    protected AmazonElasticMapReduceAsync build(AwsAsyncClientParams params) {
        return new AmazonElasticMapReduceAsyncClient(params);
    }
Construct an asynchronous implementation of AmazonElasticMapReduceAsync using the current builder configuration.

@param params
       Current builder configuration represented as a parameter object.
@return Fully configured implementation of AmazonElasticMapReduceAsync.
aws-java-sdk-emr/src/main/java/com/amazonaws/services/elasticmapreduce/AmazonElasticMapReduceAsyncClientBuilder.java