public java.util.List<MetricDimension> getDimensions() {
        if (dimensions == null) {
            dimensions = new com.amazonaws.internal.SdkInternalList<MetricDimension>();
        }
        return dimensions;
    }
<p>
A CloudWatch metric dimension.
</p>

@return A CloudWatch metric dimension.
aws-java-sdk-emr/src/main/java/com/amazonaws/services/elasticmapreduce/model/CloudWatchAlarmDefinition.java