public Boolean isReturnData() {
        return this.returnData;
    }
<p>
Indicates whether to return the timestamps and raw data values of this metric.
</p>
<p>
If you use any math expressions, specify <code>true</code> for this value for only the final math expression that
the metric specification is based on. You must specify <code>false</code> for <code>ReturnData</code> for all the
other metrics and expressions used in the metric specification.
</p>
<p>
If you are only retrieving metrics and not performing any math expressions, do not specify anything for
<code>ReturnData</code>. This sets it to its default (<code>true</code>).
</p>

@return Indicates whether to return the timestamps and raw data values of this metric. </p>
        <p>
        If you use any math expressions, specify <code>true</code> for this value for only the final math
        expression that the metric specification is based on. You must specify <code>false</code> for
        <code>ReturnData</code> for all the other metrics and expressions used in the metric specification.
        </p>
        <p>
        If you are only retrieving metrics and not performing any math expressions, do not specify anything for
        <code>ReturnData</code>. This sets it to its default (<code>true</code>).
aws-java-sdk-autoscaling/src/main/java/com/amazonaws/services/autoscaling/model/MetricDataQuery.java